How do you crimp an all copper bullet. I am trying to load some barns 275gr.
First I tried to load like the lead copper bullets.
1. Use expander die just enough to flair case mouth
2. Use seating die seat bullet at 2.26
3. Use taper crimp die set about 1/8 taper to the case
This causes the bullet to be loose but it will not come out kinda like a rimfire bullet.
The next attempt I removed the expander die and it had the same affect of a rimfire bullet.
The next attempt I removed the expander die and the taper crimp die.
The bullet looked good and seemed solid. I firmly taped it nose down on the table and no movement. Then I used the thunk test and it passed. Then I fed it out of a clip and the bullet jumped forward from 2.26 to 2.28
What am I doing wrong and how can I fix it.
Its getting frustrating.
I have had the same problem and mentioned it in a post a while ago. The problem is the mass of the bullet is great enough to be pulled from the case due to the bolt velocity during chambering. Much like a bullet puller would do. Currently I expand the case mouths for .452 bullets, but not for .451 or as with the Montana Gold — .4505. I do not flare the mouths. If you set up the Hornady dies correctly, the bullet should start straight. Maybe chamfer the inside of the case mouth, but only slightly because this is where the headspace is occurring. I crimp in the crimp groove at the rearmost portion — trying to minimize the jump. A draw back of seating the bullet out as far as we can, lessens the amount of bullet in the case — thereby reducing the amount of friction to move the bullet forward. When I use the 300 gr. Remington sized to .452 and seated to the crimp groove — I do not get any bullet movement. Just a note — while chambering factory loads to test magazines, ect. — even those bullets will move forward the 2nd and 3rd time they where chambered.
Try not to get frustrated, this is a labor of love, wanting something the factory can’t give us, accuracy, down range energy, and of the all mighty dollar and we like that, right?
Solids are a bit of a problem, but Siringo has it solved and is the easiest way to go.
A couple of other suggestions are to bond the bullet to the case. The military does this with all their small arms ammo for waterproofing and bullet pull purposes (they seal the primers too). They use a gum in the case mouths. The closest thing I have used is the gum product that tree doctors use, to scab over a severed limb; most garden stores carry it, better call ahead though. It is applied by using a pipe cleaner and better let the gum set up after crimping. I however am quite lazy and bell the cases as much as I can and then, after seating the bullet I use red Loc-Tite (Just because I have a ton of it around the shop, other colors/types may certainly be useful), and then crimp (With my hunting ammo, I seal the primers with the same product). By using a drop on a tooth pick, capillary action will suck the drop into the case and totally around the bullet, experiment with the size of the drop. There are some things to consider though. First you have to let the Loc-Tite dry, 24hrs, and second, because of the extra bullet pull you’ll have to back off of the powder some. BUT, and this is a big “but”, that extra bullet pull burns the powder so efficiently that it will allow you to use slower powders, thus lowering the pressures, thus allowing you to bring the pressures back up and thus you’ll see much higher speeds (‘lil gun is very useful and I’ve even burned blue dot very successfully, but if speed is the goal, slower powders are the trick. Keep the pressures safely up, if you don’t want to see sooting). Of course, safe reloading practices apply; sneak up on the powder charge, looking for pressure signs all along the way. All this is unnecessary on lead based bullets as enough tapper crimp can be applied, unless of course, you want to use the slower powders. The Loc-Tite trick seems to cause more bullet pull than even a roll crimp (something we can use on the 450), which is a really a good thing, in my view, that is, if you are watching for excessive pressure signs. One other problem is, with all that excessive belling, you may want to extend case life by annealing, I do this regardless. I myself do this by sinking my de-primed cases into a cake pan of ice water about half way up the case body (keeping the heat away from the bases as you could see case head separation, a bad thing), then with a torch, propane is fine, heat them up to red hot and then knock them over, the water will instantly cool the cases and bingo, annealed cases.
Regarding neck tension — I have been playing around with various techniques/bullets tonight and despite what I do, I still get some bullet movement upon chambering. The only exception is when a crimp groove is present to lock into. But even then, repeated chamberings came move the bullet forward.
However, an extra step that really helps to minimize this is to clean the inside of the case neck after the case has been sized and expanded. That will remove any trace of case sizing lubricant or powder residue that could lessen neck tension. Do this even after using a case polisher. I used denatured Alcohol on a swab. Also, depending on the bullet, I want to have between .002 and .003 inches of neck tension (inside case mouth is that much smaller the bullet).
I have done so much testing the past 2 days that my right hand is sore from screwing and unscrewing dies in and out of the press.
No mater what I do I can not keep the barns bullet from moving. I have done all that you listed above and more. I took cleaning the case one step farther, I used 150grit sandpaper to rough the inside of case just one turn not to remove much material, that helped a little but very little. I have been getting about the same neck tension as you Siringo so i increased it to .006 by using the taper crimp die before loading the bullet, but it was no help. The taper crimp can only kiss the brass or it will dent the barns bullets with decrease the neck tension.
The best results I have had came from peening the case around the bullet.
I got this idea from some 7.62×25 pistol bullets i have for my cz52. The casing has three peen marks half way down the neck I suspect to increase reliability for the submachine gun the round was made for. For people that are unfarmiliar with the 7.62×25 it is a bottle neck pistol bullet.
Following the idea of the peen marks I took a small nail set and put 3 peen marks on one case and 4 on another. The first cartridge started at 2.262
after the first chambering it jumped to 2.267 second 2.269 third 2.270 fourth 2.271 faith 2.274 sixth 2.277 The second cartridge with 4 peen marks started at 2.260 after the first champering it went to 2.263 second 2.264 third2.265 fourth 2.265 faith 2.266. The down side to this is that I have no way to be consistent with the depth and location of the dents. If someone knows how please speak up.
The last attempt to decrease bullet pull I used was to set the bullet deeper to catch the crimping groove. I didnt want to increase the distance the bullet had to jump to get to the lands or decrease case capacity but Im at the end of my ideas. I seated the bullet to 2.215. The outside of the case mouth before the bullet was .476 after bullet seated .479 after taper crimp .476 . The first chambering it went to 2.225 second 2.231 third 2.240.
As a reference I used a factory round and tested it too. It started at 2.234
after the first chambering it was 2.242 second 2.250 third 2.258. about the same as when I seated it to the crimp grove.
I then checked case capacity with H110 with the 275gr Barnes set to a depth of 2.215. First i weighed the case with seated bullet 445.7gr then added the powder 484.6gr. This gave me a difference of 38.9gr and confirmed after powder measured alone.
I need some help!
When i try to cycle some reloads through the chamber they are getting stuck, and i can not figure out why. I used the thunk test for the first reloads and they made a good sound when they fell into the chamber. my second reloads were ok but not as good as the first batch. This round will not eject when i cycle them i have to use a cleaning rod to tap the round to get it to dislodge Very carefully.
There is a bulge at the bottom of the bullet in the brass and i wonder if this is the problem. I have tried a few things and can not figure it out. First i tried not to use the flair die no help. I tried a heaver taper crimp but i belive that the case mouth was not seating. I tried using less taper crimp no help.
I tried resizing the loaded round but it drove the bullet deeper into the case.
If you are using longer bullets in this batch of loads, you may need to neck ream to account for the thicker brass below where you were seating before.
As usual, apply sharpie marker to the offending case and chamber it.
The sharpie marker will rub off where it’s tight.
10-4, this is great advice and you need to do as advised and get back with us. You shouldn’t need to ream, but Randal makes his point with the longer bullets.
Consider. The reason for the great accuracy with some of these loads is because Bushy holds tolerances that the competition only dreams of and it’s a possibility that your chamber is being touched by brass that is flowing, hence what Randall is trying to ascertain, with the sharpie.
Question, when you resize the loaded reloads is the bullet seater coming into contact with the bullet as you resize again, causing the bullet to be further seated down into the case, just as the taper-crimp is going on? Make sure that the re-resize step is a separate operation, screw out the bullet seater so it can’t possibly touch the bullet. Your cure is proably one of these thoughts ( if it turns out that Randal wins, then he owes me a loaded pizza and if I win he owes me two pizza’s…I love this game), once you get it and understand what’s really happening, you’ll be back in Shooters Heaven again…t
Two things — one, the reloaded cartridges are out of round. Factory stuff is pretty straight — I have had issues with concentrity (spelling) with reloads. Also, I have reloaded some of mine stuff up to 5 times. The brass does grow. Factory says OAL to be 1.7″ max. Trim to length per factory is 1.69″. This can effect crimp.
Generally speaking, if the crimp die is actually made to spec you can not over crimp, using a taper crimp die. 1.69″ is way to short, in my opinion, and is Hornady’s standard. That’s .010″ and is the standard for the 45ACP/9mm lugar (auto pistols) ect. My orginal standard to Bushmaster was 1.700″ plus nothing, minus .003″ or 1.697″ and will make your groups even more accurate (as if accuracy ever was a problem).
You really need to do the sharpie test. Close-up pics labeled 12-3-6-9 o’clock would give us a chance to see what is going on. I’m intrigued about your run-out (concentricity). How much is it? What model of press do you use?
I trimmed 100 cases last night. Before trimming, most of them varied between 1.690 and 1.697. The once fired Hornaday cases were 1.690 to 1.692. Most of the other cases had been reloaded 3 times. Seems that Hornaday is making these cases on the short end.
I am using an RCBS press w/Hornaday dies.
Well, .010″ is not really short, just more than I like. There are production realities that we’ve just got to put up with, but we as custom reloaders can hold much tighter standards. Having said all that, Hornady really has made some mighty fine accurate fodder, you must admit.
As an after thought, make sure you full length resize before you trim and then trim to the shortest cartridge you wish to use, saving the rest for other uses.
The floating seating die from Hornady is supposed to assist in bullet alignment during seating. I have not found any variation in seating depth with my dies. However, I am not sure how straight the reloaded cartridges are compared to the factory rounds. There are signs of a bulge on the reloaded round that does not seem to exist on the factory round – even though the OD diameters are the same between the two.
I do not use the seating die for crimping, but the supplied taper crimp die. I too am wondering how much crimp is required. I have noticed that if the bullet is not crimped enough, upon chambering, the bullet would move forward (if crimped in the forward portion of the crimp groove). This would have an effect on the accuracy. This even happens with the factory ammo. I was running the rounds in and out to test magazines and after a time or two the cartridge OAL would change — growing longer. The bullet has enough mass and the bolt speed is high enough that upon chambering the effect is that of an inerta bullet puller.
Here are some measurements using my Hornady dies:
1. After one firing, sized and expanded — Inside diameter of case =.450″
2. After one firing case wall thickness = .0135
(neck tension = .002″)
3. OD at edge of crimp = .476″
4. Case is somewhat tapered in bullet area, but OD just before crimp in .480″
Based on these measurements, I am crimping into the crimp groove .002″ (240 gr)
Note that the crimp edge on the factory round is .477″. So the factory is crimping into the 250 gr bullet .001″.
The factory loads are very accurate. Using the same bullets, primers and powder — the single most significant item to duplicate factory accuracy is the reloaded round has to be just as straight. I do not have a way to measure the runout, maybe some of you can. Also, I know my measurements are a thousand or two off factory, but it was with my caliper just to show a difference. Based on the factory drawing, they are crimping into the bullet .001″.
I’m not sure on the Point of impact, this go ’round I didn’t shoot any factory rounds, I just shot a bunch with the 39.3 gr load and the bullets seated at 2”, 2.05″. 2.1″ and 2.15″. The 2.05″ seemed the best group and each length had a different point of impact.
The following are five rounds of each load at 100 yrds using Montana Gold .452 250 gr FP bullets and H110 powder with an OAL of 2.15″.
load velocity group
Factory 2150 fps 1.24”
38.5 grs 2045 fps 1.35”
39 grs 2095 fps 2.79”
40 grs 2135 fps 2.13”
41 grs 2235 fps 2.65”
41.5 grs 2305 fps 4.95”
42 grs 2346 fps 2.74”
42.5 grs 2310 fps 2.34”
43 grs 2350 fps 3.83”