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FormulaXFD posted:I can throw in the mass of the weapon and moment about pivot point too. Internal mechanics of burn rates are just that, internal. The gasses have some influence (e.g. muzzle brakes) but the overall system still falls within 98% as described. hmmmm... I have a senior engineering project coming up here in January.
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| # ? Jul 17, 2011 06:56 |
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TRAP SET!
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| # ? May 23, 2013 01:21 |
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shalafi4 posted:hmmmm... I have a senior engineering project coming up here in January. You have my moral support in this!    In other reloading related news (for me) I have decided to impulse buy this:  A dillon strong mount. I hope to be able to fix the mess that is my reloading bench with this bit of metal 
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| # ? Jul 17, 2011 09:24 |
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shalafi4 posted:hmmmm... I have a senior engineering project coming up here in January. Please do this  FormulaXFD - I am no maths wizard by any stretch of the imagination, but while you might get a similar result on recoil energy between two different loads, FEEL may be different. As you mentioned slight weight is very important in the amount of recoil a shooter experiences. But hell, keeping the same load you can change how recoil feels by altering spring rates. Both recoil and main/striker springs. To me a gun sprung lightly has less felt recoil, even though slide speed is up and it impacts the end of its travel much more harshly than a heavily sprung gun. Not to mention that heavily sprung gun is going to dip down much more as the slide slams forward. I guess it really comes down to this - Tinker around with different powders and bullet rates to find a load that shoots well in your gun. In your load experiments you'll come across a combo that not only shoots accurately but you like the FEEL of in a certain gun. Repeat for other guns. It's not extra work because shooting is fun 
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| # ? Jul 17, 2011 14:35 |
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shalafi4 posted:hmmmm... I have a senior engineering project coming up here in January. I would be glad to sponsor you with some semiconductor parts from my work. If you decide to do it, hit me up with a PM. We do a lot of different things, including accelerometers. http://www.analog.com quote:FormulaXFD - I am no maths wizard by any stretch of the imagination, but while you might get a similar result on recoil energy between two different loads, FEEL may be different. As you mentioned slight weight is very important in the amount of recoil a shooter experiences. But hell, keeping the same load you can change how recoil feels by altering spring rates. Both recoil and main/striker springs. To me a gun sprung lightly has less felt recoil, even though slide speed is up and it impacts the end of its travel much more harshly than a heavily sprung gun. Not to mention that heavily sprung gun is going to dip down much more as the slide slams forward. Without a doubt perception affects the way the user "experiences" the recoil. I would never argue that. You're also right about the recoil spring used for the slide; one with a ridiculously high spring rate is going to transfer more total energy to the receiver (and thus to the user) than a slide with a ridiculously low spring rate which lets the slide "crash" to the rear stop. There are quite a few things which can be modified on the weapon itself to adjust the way the recoil is expressed, but when considering loads, it's best to modify one thing at a time, and the cheapest route is usually the ammo first.
FormulaXFD fucked around with this message at Jul 17, 2011 around 17:48 |
| # ? Jul 17, 2011 17:33 |
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needknees posted:Winchester WST is another option. I LOVE Winchester Super Target. It meters great and burns cleaner than anything else I've used. I use it in 9mm, 40sw, and 45acp. Next time I need to make 38spl, I'm going to try it in that, too.
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| # ? Jul 17, 2011 17:54 |
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FormulaXFD posted:I would be glad to sponsor you with some semiconductor parts from my work. If you decide to do it, hit me up with a PM. We do a lot of different things, including accelerometers. I definately will I think we order stuff from analog occasionally at work from you guys already. (I work in the machine/helpoutthecluelessgradstudentswiththeirdesigns shop for my engineering department)FormulaXFD posted:Without a doubt perception affects the way the user "experiences" the recoil... Here's a thought... use 2 sets of accelerometers. I'd have to build a holder on rails for the handgun so it would recoil the same each time. (picture a miniature artillery recoil system minus the pneumatics) One set would go on the slide one set would go on either the grip or the carrage holding the gun. that way you'd see 1) how fast the slide recoils 2) how fast the entire system recoils (using maths to subtract the addional weight from the carrage) thoughts?
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| # ? Jul 17, 2011 19:59 |
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FormulaXFD posted:If you want/need low recoil, punch in your values into the equation below: I'm pretty sure that recoil is quantified through momentum, not kinetic energy. A very high energy, but lightweight round is going to have less recoil than a heavy round of the same energy. Also you never bothered calculating the effect of the firearm's mass, which is significant, and not that hard to calculate. And, of course, felt recoil is a function of jerk, which you would have great difficulty isolating from an energy analysis. I hate to sound like a dick, but where did you learn this stuff?
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| # ? Jul 17, 2011 20:14 |
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Some mixed headstamps of ammo I'm reloading. Lots of Israeli surplus but the 53 marked top row is one of a kind in the ~1500 rounds I've shot so far of it. Bottom row common WWB, S&B, 93 Norinco which I'm a little worried about because every shell has a line on the brass near the base. Anyone care to comment if it's OK or I should toss it? All my Norinco shells look like this. And some NATO stamped stuff. I thought it may be that mega hot ATF warning letter Hirtenberger of which I bought a case of but I think that was L-something.  Installed small cylinder. Note: The gap between cylinder and housing is cut to very precise tolerances! (and can cut the crap out of you if you're not careful installing). Also got in some Rem 124gr 9mm and bought FMJ and forgot, that doesn't include the base of the round, drat it. I bought these to run through a ported barrel suppressor so need a good jacket and would have just gotten a TMJ if I had remembered the difference. Lyman ultrasonic cleaner does OK with vinegar and water but got some cleaning solution at whatever goon's advice so looking forward to that. The gear and toys with reloading is fun stuff. I can see how one could get into this as a side hobby to shooting. E: I somehow managed to save a dozen brass plated steel cases and resized and primed 4 of them before realizing. It was the S&B Range Safe ammo. I just threw them away when I discovered it. Also if anyone bought any of that Adcom 9mm surplus the pockets are too small to get a small primer in there, at least with normal force. Good thing I only had a bit of the brass out of the case. Sten Freak fucked around with this message at Jul 17, 2011 around 22:03 |
| # ? Jul 17, 2011 21:59 |
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Sten Freak posted:Also if anyone bought any of that Adcom 9mm surplus the pockets are too small to get a small primer in there, at least with normal force. Good thing I only had a bit of the brass out of the case. Crimped primer pocket, maybe? I don't have the first idea what that marking on your cases is. If it were a sign of case separation, I'd expect it to be white, since what you're looking for there is thinning metal. Does it scrape off with a fingernail?
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| # ? Jul 17, 2011 23:27 |
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thermobollocks posted:Crimped primer pocket, maybe? The primer pocket is not crimped with the 4 little divots like I've seen on some surplus. Unless it's crimped in some other way. It's from UAE and maybe it just slightly out of tolerance? The inside primer pocket diameters were .005-.006 smaller than my other brass. No biggie as I have a ton of brass so I'll just recycle it. No it doesn't scrape off, and it's on all the Norinco cases (only the Norinco). I may just recycle it too, unless you want it and I can give it to you next goonshoot. Using the manual I'm starting with minimum load 5.2gr of Unique with my 124gr bullet. Loaded 5 cases. I expect them not to fully work a Sten bolt but we'll see.
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| # ? Jul 18, 2011 00:20 |
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Thanks for the reply re: smokey nose. Yes this was indoors. I'd never heard that about less powder meaning more smoke but that is what evidence I'd seen first-hand thus far so I don't doubt it's true. I've heard of folks dialing these loads up to 3.6-3.8 gr, so I can easily go above 2.6 if that will get me less smoke. It's not exactly hard to shoot at 3-3.2gr. I have some Clays an Universal Clays on hand, too, but like needknees said Solo1k is a very well-regarded powder for 147gr 9mm. I haven't tried either of those with 9.
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| # ? Jul 18, 2011 00:33 |
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Sten Freak posted:The primer pocket is not crimped with the 4 little divots like I've seen on some surplus. Unless it's crimped in some other way. It's from UAE and maybe it just slightly out of tolerance? The inside primer pocket diameters were .005-.006 smaller than my other brass. No biggie as I have a ton of brass so I'll just recycle it. Some crimps are just a stamped inset around the edge of the primer pocket. It'll look like the 2nd from the right on the top row of the photo you posted of the headstamps. (the right LC one as well)
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| # ? Jul 18, 2011 07:19 |
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Male Man posted:I'm pretty sure that recoil is quantified through momentum, not kinetic energy. A very high energy, but lightweight round is going to have less recoil than a heavy round of the same energy. Also you never bothered calculating the effect of the firearm's mass, which is significant, and not that hard to calculate. Well, I worked it out and I'm half wrong. Recoil itself as it pertains to the weapon is a matter of kinetic energy. You're wrong there. Linear momentum is the correct translation of velocity relation between bullet and slide which is where I was wrong. I'll make a note of it not to post math when I'm tired. For the firearm's mass, its contribution to the slide can be neglected when it's a semi-auto pistol. If it's a revolver the math gets quite a bit easier. Felt recoil is a function of the user's senses, including the actual kinetic energy of the firearm. Expressing the actual recoil where one includes the user of the weapon is not something with "great difficulty" either. For what it's worth, and if anyone is interested, I actually did out the formal math for it so I can post it. My error came from the work equations where I made a bad assumption. (Total work having to be conserved) Correcting for that though, it all falls into place. That being said, to completely be a dick, for the amount of  going on I'd expect to be shot down with some actual math or something more tangible than "guy on the internet says you're wrong." As for me, working on my Masters in Mech Engineering. So yes, holy poo poo I made an error. Edit: (Specifically, since m_b*v_b ~= m_s*v_s its quick to jump to try and use the two interchangeably.) Edit2: Mess of calcs here FormulaXFD fucked around with this message at Jul 18, 2011 around 08:44 |
| # ? Jul 18, 2011 07:41 |
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These are my first set of reloaded rounds ever. 45. ACP 185 grain, I used N-340 vihtauouri powder. I'm pretty excited this just going to be a test run. The stated velocity FPS is 1032 though my loads were lighter on purpose so these should be less powerful. The real joy is having them work can't wait.  Testing tomorrow. DropsySufferer fucked around with this message at Jul 18, 2011 around 10:12 |
| # ? Jul 18, 2011 10:09 |
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If you are doing some tests with felt recoil, remember to do double blind tests with a control group shooting something retarded like a .50 bmg without muzzle break
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| # ? Jul 18, 2011 10:19 |
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shalafi4 posted:Some crimps are just a stamped inset around the edge of the primer pocket. It'll look like the 2nd from the right on the top row of the photo you posted of the headstamps. (the right LC one as well)  The Adcom could very well be crimped then.
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| # ? Jul 18, 2011 13:16 |
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DropsySufferer posted:These are my first set of reloaded rounds ever. 45. ACP 185 grain, I used N-340 vihtauouri powder. I'm pretty excited this just going to be a test run. The stated velocity FPS is 1032 though my loads were lighter on purpose so these should be less powerful. The real joy is having them work can't wait. I didn't know they made jacketed semi-wadcutters. That's pretty rad. Did you try manually cycling them through your gun to make sure they'll feed? Also, how light are they? With autoloaders, you'll find that underneath a certain value in the given powder charge range, your ammo might not cycle.
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| # ? Jul 18, 2011 17:12 |
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FormulaXFD posted:Well, I worked it out and I'm half wrong. Recoil itself as it pertains to the weapon is a matter of kinetic energy. You're wrong there. Linear momentum is the correct translation of velocity relation between bullet and slide which is where I was wrong. I'll make a note of it not to post math when I'm tired. Dude calm down, no one wants to see us get into a slap fight over who's the greatest at physics. I was (and still am) legitimately confused why you'd use energy analysis for the system when--being as this discussion was prompted by powder burn rates--you want time dependence, and I was suggesting some first thoughts about how I'd approach the problem. I was, admittedly, a little barbed when I questioned your methods. That was uncalled for. I said I wasn't trying to be a dick, and I'm not, so I apologize if I came off that way. Knowing that you come from a mechanical engineering background explains a lot about how you're approaching the problem. As for my own math, I'd try, but I don't know enough about the chemistry to make a good attempt. I'd end up needing to make a terrible assumption about powder burning (like exponentially decaying burn rate) in order to be able to quantify the pressure in the chamber (via the thermodynamic identity, under the assumption of an adiabatic process).
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| # ? Jul 18, 2011 17:36 |
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Sten Freak posted:Ah, I see it now. That would explain why the 53 was harder to prime too yea some of those crimps are sneaky ! the worst are the ones that are only partially crimped "oh it's just a little stiff" as you shear half of the side of the primer off 
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| # ? Jul 18, 2011 19:48 |
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Male Man posted:Dude calm down, no one wants to see us get into a slap fight over who's the greatest at physics. I was (and still am) legitimately confused why you'd use energy analysis for the system when--being as this discussion was prompted by powder burn rates--you want time dependence, and I was suggesting some first thoughts about how I'd approach the problem. I was wondering about this as well, especially since needknees JUST posted a thing about how different powders cause different impulses which affect felt recoil. This difference has been observed empirically, so unless there's a mass delusion among reloaders regarding powder burn rates those observations need to be accounted for. Also I think there are enough people here from math & physics to laugh at anyone who appeals to their own authority as a mechanical engineer. poopgiggle fucked around with this message at Jul 18, 2011 around 19:56 |
| # ? Jul 18, 2011 19:54 |
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poopgiggle posted:This difference has been observed empirically, so unless there's a mass delusion among reloaders regarding powder burn rates those observations need to be accounted for. To be fair, I wasn't going blind shooting the different reloads. poopgiggle posted:Also I think there are enough people here from math & physics to laugh at anyone who appeals to their own authority as a mechanical engineer. Can I appeal to the back of the Lyman book, which lists powder mass in its free recoil energy calculation?
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| # ? Jul 18, 2011 20:23 |
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Heintron posted:If you are doing some tests with felt recoil, remember to do double blind tests with a control group shooting something retarded like a .50 bmg without muzzle break Once the charge exceeds a few percent of the bullet's mass you can't use the approximations I described. So even something like .223 requires incorporation of ejected gasses as a part of the system. Male Man posted:I was (and still am) legitimately confused why you'd use energy analysis for the system when--being as this discussion was prompted by powder burn rates--you want time dependence, and I was suggesting some first thoughts about how I'd approach the problem. I was, admittedly, a little barbed when I questioned your methods. Burn rates do influence the system, I'm not saying otherwise. But when the charge's mass is small compared to the projectile (~5%) you can neglect it for the big picture. The impact of burn rate is then conversion of charge mass into gas. If 100% of the charge is burnt, the gas expulsion will have a higher contributing factor to the slide's velocity than 50% burnt charge. But the 50% expended charge will keep burning as vented which then gives a flash. Flash and boom obviously influence perceived effects of a round. Powder chem is outside of my field, but you can make some general considerations for its performance based on conversion (if you're familiar with thermo then you can think of it similar to the Otto cycle with an imperfect combustion). poopgiggle posted:Also I think there are enough people here from math & physics to laugh at anyone who appeals to their own authority as a mechanical engineer. It's not like he asked where I'm coming from or anything  Besides, I did not use my current schooling as a BS appeal to authority, I used the math to back it up. Anyway, math has been given, the error corrected, I'll dismiss myself from continuing on this.
FormulaXFD fucked around with this message at Jul 18, 2011 around 20:39 |
| # ? Jul 18, 2011 20:36 |
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thermobollocks posted:Such as? If your loadbook has the weight and profile of bullet listed, I say go for it. The Lyman book has a ton of cast bullet data. The AA manual even has data specifically for Berry's, and those are a great value for a low-mid volume shooter. Cast bullets issues not found with jacketed bullets =================================================== hardness may vary between batches lube type may vary between batches cast bullets must be limited by speed and pressure, not just pressure. barrel must be inspected more often for leading cast bullets often require a more expanded case mouth (some manufacturers make separate "cowboy" dies just for cast bullets to compensate for this) cast bullets are more susceptible to feeding ramp damage This doesn't include the additional issues when you begin to cast your own. As I said: not major issues, but best avoided when someone is just learning how to use a powder scale, press, priming tool, etc. cast lead bullets, especially roll-your-own, are an awesome idea once a beginner has loaded at least a few boxes of ammo using FMJs.
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| # ? Jul 18, 2011 20:37 |
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This is probably a more appropriate spot for this question then the long range thread. Back story buying a rifle in .280 rem. Want to make some good rounds, so what dies do you guys prefer, and what other reloading stuff is nice to have, other then the basics?
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| # ? Jul 18, 2011 20:46 |
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Ferris Bueller posted:This is probably a more appropriate spot for this question then the long range thread. Back story buying a rifle in .280 rem. Want to make some good rounds, so what dies do you guys prefer, and what other reloading stuff is nice to have, other then the basics? Tools like the concentricity gauge, headspace gauge (RCBS Precision Mic), and vernier micrometer let you check the process with some certainty. I like my Redding dies and Forster press; the combination makes for good accuracy. I enjoyed this book as an easy read that helped me understand loading rifles for accuracy. If you're a seasoned rifle reloader you may not get much from it, but as a supplement to The ABCs of Reloading it's good.
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| # ? Jul 18, 2011 21:18 |
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No, I wish I had tried manually cycling the rounds beforehand. My ammo worked as best as I could hope for. The problem I had was the rounds usually wouldn't cycle after each shot. I'm still extremely pleased aside from that kink everything worked as planned. One round got stuck in the chamber because I was having to pull back the slide and load the rounds one by one. I'm not sure why these rounds had trouble entering the chamber and cycling. The grain is 185, the powder charge was .70 cc. My first guess is that I'm seating the bullets incorrectly, but it seems logical they should be pressed in as far the pictures show. One thing about these bullets is that us there no line or anything to indicate how far to seat the bullet.  Reading now weight is an issue it seems. Oh well I only have a 100 of these then I'm going with more traditional bullets. thermobollocks posted:I didn't know they made jacketed semi-wadcutters. That's pretty rad. DropsySufferer fucked around with this message at Jul 19, 2011 around 04:26 |
| # ? Jul 19, 2011 04:10 |
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DropsySufferer posted:No, I wish I had tried manually cycling the rounds beforehand. My ammo worked as best as I could hope for. The problem I had was the rounds usually wouldn't cycle after each shot. I'm still extremely pleased aside from that kink everything worked as planned. Paging IR35, IR35 to the reloading thread for .45 ACP chambering issues.  Did you crimp them at all? If you flared the case mouth too much, then not only can the case mouth hang on your feed ramps, but also the rounds might not fit entirely in the chamber. Also, if there's not enough tension holding the bullet in, it can wiggle its way out (annoying) or seat itself back (boom!). Also, I have no idea where you're supposed to crimp a bullet like that. One more thing, you said the charge was 0.70cc of N340? What is that in grams or grains? Because powder settles, actual mass is by far the preferred measure. Things like vibration can throw off your charges by quite a bit, and if you only have powder scoops, you should probably be weighing them out every time. If you didn't get any feeding jams, then it seems the bullet shape wasn't the problem, but rather the charge not being enough to cycle the gun. If it helps any, the VV loading manual indicates a starting load of 0.46 grams (7.1 grains) of N340 and a max load of 0.50 grams (7.7 grains). The COL it gives is 31.5mm (1.240 inches) for a 185gn Speer total metal jacket semi-wadcutter, which is what you have.
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| # ? Jul 19, 2011 04:45 |
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thermobollocks posted:Paging IR35, IR35 to the reloading thread for .45 ACP chambering issues. I did crimp one of my test rounds and looking at it now I see that's the one that got stuck in the chamber, every other round fired just fine aside from feeding issues. You can't see the error in the photo, but the crimping pushed the brass a bit expanding it too much. From those pictures that's how far I seated the bullets as that's what seemed logical to me. Seat the bullet until it reaches the head. Since I only got one stuck round and that was due to crimping. I suspect the real problem is weight. Interesting, I have Lee's Modern reloading volume as my reference and the loads do not indicate weight, just volume CC. I found out quickly I needed a good scale that measures CC exactly but that's in the mail at the moment. I have tools that give me an approximate CC but not exact. With your information I can weigh my loads and make sure the powder amount is perfect. What other books would be useful for more data? I went with a lee handloader as a starter. Very soon I'm going to get something better, it's simply not precise enough and seating bullets is extremely time consuming. DropsySufferer fucked around with this message at Jul 19, 2011 around 05:53 |
| # ? Jul 19, 2011 05:44 |
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DropsySufferer posted:Interesting, I have Lee's Modern reloading volume as my reference and the loads do not indicate weight, just volume CC. I found out quickly I needed a good scale that measures CC exactly but that's in the mail at the moment. I have tools that give me an approximate CC but not exact. With your information I can weigh my loads and make sure the powder amount is perfect. O.o it lists values in grains as well.
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| # ? Jul 19, 2011 05:54 |
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shalafi4 posted:O.o it lists values in grains as well.  How the heck didn't I see that part.
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| # ? Jul 19, 2011 06:14 |
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DropsySufferer posted:
It's not the weight, it's the shape. Semi-wadcutters are notoriously hard to feed in some guns. I went through a thousand of them in my P220, never found a load that worked consistently for me, switched to a flat-point profile and it feeds everything. Play around with the seating depth to see if you can find one that works. If you can't work it out by the time you get through your hundred, just buy bullets with a normal profile.
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| # ? Jul 19, 2011 13:29 |
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Schlack-Schlack, BANG! Schlack-Schtbt...Uh Oh:    When I was seating my bullets (.308 Hornady 170 gr. SPFN) in my 30-30 brass after full-length sizing, one dropped right to the powder. After fiddling with it for a moment and getting it to the proper COAL, I decided to turn it into a test of the factory crimp die. It ran through the die fine and I checked it about five times before deciding to take it to the range. It was the second round in my magazine and decided to telescope on the way into the chamber of my '94. Surprise, surprise. Moral of the story: If your brass/bullet/whatever goes hinky at any point, just toss it.
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| # ? Jul 19, 2011 17:23 |
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Butch Cassidy posted:Moral of the story: If your brass/bullet/whatever goes hinky at any point, just toss it. The bullet was too skinny, or what?
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| # ? Jul 19, 2011 19:44 |
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or really worn brass? (ie neck brass is too thin?)
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| # ? Jul 19, 2011 22:52 |
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Sanity check: Is it a terrible idea to make your own blanks? I picked up a golf ball launcher but I can't find blanks anywhere, local or online. e: I just found some at Widener's, but the question still stands. It'd be nice to be able to re-use the brass - would something like a wax or paper plug and a light roll crimp be feasible? vvv .223 or 7.62x39. I'm thinking of making a dedicated golfball AR top half using the cheapest barrel/upper I can find. Uncle Caveman fucked around with this message at Jul 19, 2011 around 23:19 |
| # ? Jul 19, 2011 23:11 |
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Uncle Caveman posted:Sanity check: Is it a terrible idea to make your own blanks? I picked up a golf ball launcher but I can't find blanks anywhere, local or online. What caliber are you thinking? because I have a fireforming recepie for 5.45x39 (ie 223ish) that would make for a good blank
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| # ? Jul 19, 2011 23:17 |
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Heintron posted:You have my moral support in this! I really like mine. I feel like it was ok for me to spend a bit of money setting up my xl650, since I expect to be reloading on it for decades to come.
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| # ? Jul 20, 2011 00:32 |
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thermobollocks posted:
There is a faction that claims that volume is the best way to measure powder charge. The idea being that lot to lot variation in density make weight suspect. I have no real opinion in the matter but using a scoop, if you can master the technique, can produce very consistent charges.
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| # ? Jul 20, 2011 00:42 |
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bunnielab posted:There is a faction that claims that volume is the best way to measure powder charge. The idea being that lot to lot variation in density make weight suspect. I have no real opinion in the matter but using a scoop, if you can master the technique, can produce very consistent charges. Is it the bulk density or the density of the actual particles that varies? If it's the former, then it's really best to measure by weight.
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| # ? Jul 20, 2011 01:08 |
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| # ? May 23, 2013 01:21 |
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Daikon posted:I really like mine. I feel like it was ok for me to spend a bit of money setting up my xl650, since I expect to be reloading on it for decades to come. My setup atm:  Reloading Bench by Heintron, on Flickr Kind of wish I had a higher ceiling right now
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| # ? Jul 20, 2011 09:08 |
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