370g gas check Cast Perf in .50 AE Desert Eagle

[jmden]

Been shooting (every other round is a 300g Hornady XTP)these after PC'ing and resizing to .501 for awhile. I have an intermittant failure to return to battery and have narrowed it down, I believe, to there being a 'ring' of lead shed from the bullets and found at the far end of the chamber, right where the case mouth should be headspacing. Sometimes I'll see a fragment of this 'ring' (Edit here to end of sentence as I didn't finish the sentence) sticking out into the barrel from where the end of the chamber where the case mouth should be headspacing.

Here's a pick of a partial 'ring': https://www.flickr.com/photos/94284395@N07/shares/32E6Xz

Any ideas what's going on?

Thanks.

[06ackley]

Try seating the boolit and crimping separately.I also had this and when I crimp in a separate step it goes away.

[jmden]

Thanks, 06ackley. My Lee seating die is also the crimp die and with these boolits with that gas check, I find that I need to do a slight case mouth expansion before seating or the boolit can get damaged during seating.

Should I find a separate crimp die for this application...? I'm doing a very moderate crimp now as I want plenty of case mouth available for proper headspacing.

Edit: Sounds like maybe I should use the seater die but adjust in such a way as to do the crimping operation in a separate step.

[06ackley]

Yep you can use the same die just crimp it after you seat it.Hope that takes care of it for you.By the way for some reason the 50ae is one of my favorite pistol rounds.

[jmden]

Thanks. Yes, I'm really enjoying it to. Have you come to understand what that happens when you perform both steps at once vs. separately? Trying to wrap my head around what's going on here...

[xr650]

When you seat and crimp in one step, the boolit is still moving as the crimp is formed. This can allow the brass to dig into the lead. This shouldn't happen with a crimp groove.

When you crimp in a separate step, the brass just folds over the top of the lead.

[06ackley]

Yep what xr650 said.

[jmden]

This bullet does have a crimp groove--if you were shooting it in a 500SW. Too long of an OAL to fit in a .50AE mag. I use an OAL of 1.575, to help make sure there's a little space to help the rounds move up the mag and that's about 10 thou less than book 'max' OAL for that round. But this round headspaces on the case mouth so I need a nice, square case mouth that doesn't crimp too much. I've found a fairly moderate taper crimp it all that's needed to keep this PC'd bullet in place.

So is it the brass digging into the lead that somehow forms that 'ring' in the picture linked to above? How does that 'ring' get created and then separate from the bullet and either get stuck where the casemouth should be headspacing or sometimes a chunk of it is actually in the barrel creating an obstruction.

I've got to solve this issue or I won't be shooting cast in this thing. Haven't had a chance the last couple of days to load for it again, but will try to Monday or Tuesday. Thanks for the input.

[06ackley]

When you crimp and seat at the same time the brass is cutting that small ring off the bullet and causes rounds not to seat.Run your fingernail or knife around the edge of your rounds and see if it comes off.If it does they will chamber.That is why I separate the crimp and seat operation.My boolit also has a crimp ring and still did it until I separated the steps.Try doing them separately and id bet you wont have that problem anymore.

[jmden]

Well...I've tried this with no crimping at all with a few rounds AND with doing seating and crimping (light to moderate) in separate operations and I'm still getting a ring of lead that typically stays in the chamber right where the case mouth would otherwise be making contact. I haven't had any failure to chamber issues, but I've been pulling the barrel off after every cast round fired (alternate jacketed and cast rounds to try and minimize any potential lead build up in the gas system) to inspect the chamber and not letting that ring build up further (have to pull it out with a dental pick) so I suspect that may be why I have not had any more failure to return to battery issues.

I'm at a loss at this point. I have a batch of new Starline brass to play with but I don't think that's the issue. I'm prepping brass about as carefully as possible I believe. I've thought about doing a heavy crimp, but can't conceive as to why that would help here and am concerned I might deform the the cast bullet. I pull the barrel and check the rounds before firing to make sure that they fall in and out of the chamber with no issues, but these same rounds will leave the now infamous lead ring...

Open to ideas here...

Thanks.

[jmden]

Another member suggested belling the cases more before seating. I'd done so minimally to get a bullet started, but belled more to ensure the case mouth isn't scraping off PC and lead on it's way up the bullet. Will test soon.

[jmden]

Since last post I have tried cases that were belled more, such that a little more that 1/16" of base of bullet would advance into the case on it's own. Seemed like a lot of belling to me. Didn't matter, still got the lead ring. Tried this with brand new, sized, trimmed brass with same result. Every cast round leaves a lead ring at the end of the chamber where the case mouth should be headspacing at the end of the chamber. Then the next round won't headspace where it should. Then partway through a mag, I'll get a failure to return to battery and this is shooting a jacketed bullet every other shot in the mag. I guess this is because of multiple rings building.

Here's pic of the rings I picked out of the chamber after each cast round fired today:

https://www.flickr.com/photos/94284395@N07/shares/38Ju5W

Other thing I thought about is slugging the barrel to make sure that the .501 sizer I'm using on these boolits is actually what I need. Is there a kit or procedure for doing this?

There is something going on here that I'm missing. Sure would like to figure this out. This is a super hard hitting dangerous predator round and I'd sure like to get it working.

[44man]

Try a harder boolit. You might be expanding yours too much that also expands the brass to the chamber walls. That might leave the sharp throat edge standing proud of the brass.

[jmden]

Talked to who I think is the owner of Cast Performance today. In order to PC these, as they come with wax on them, I boiled these in water for quite a while and skimmed off the floating wax bit by bit. This may have softened the boolit from 21 Brinell hardness from their heat treating to 15-16. Perhaps that could be a cause of this? I do have an original waxed bullet or two, so will try that and see what happens.

The gentleman at Cast Performance said he could send me unwaxed bullets so they'd be ready to PC. But, in thinking about it, wouldn't putting these boolits in an oven to PC them cause them to soften as well?

[06ackley]

Well im not sure but I think they are hard enough.I know I am shooting mine not the 370gr you have and I have them around 12 hard.Once I crimped separately my problem went away but not sure whats going on with yours.Somehow when your seating or crimping its cutting the lead.

[jmden]

Would it have something to do with the Lee die? Should I try a different brand? I've had an issue with the bullet seater plug in that die where it would, on this cast boolit with a compressed load, deform and round off the edges of the flat nose. Again, a compressed load thus causing the deformations.

I've had Lee build me three different custom seater plugs and none of them worked for various reasons on this cast bullet. The best I could come up with was just to take the standard seater plug and file off the end of it (file off the concave part that would otherwise rest on the ogive on most jacketed bullets, but wasn't wide enough to get around the wide flat nose of this 370g boolit and would deform the edges of the flat nose) about 1/8" or so until it was flat. This flat faced seater plug then would rest directly on and push on the wide flat nose of the boolit to seat it in this compressed load. This seems to work great to seat the bullet.

I don't think this flat faced seater plug changed much in terms of the dimension of how far the seater plug needs to be advanced into the die for seating (in other words, could that be causing a/the problem) because the amount I filed off to make it flat basically puts the meplat of the cast bullet at the same point as the meplat of most jacketed bullets would be at with the stock bullet seater.

[jmden]

Well...went and shot one of these original, waxed, gas-checked, stock bullets, with no PC (not boiled to get wax off and not heated to PC) and...no 'ring'. Other than possibly being harder, I'm not sure what to make of this. I'm glad there's some glimmer of success with this. If, as I've been doing, I run a jacketed bullet ever other round, I'm not too worried about the issue of lead fouling, especially with this harder bullet, but would appreciate thoughts on that. This is a very stout load with this 370g bullet doing 1475fps MV. I wonder if the pressure this very heavy +P+ load produces is part of the problem. I'm going to order another box of these and see what happens.

[jmden]

Shot a few more today and no ring. The DE functioned fine going through a mag quickly. Still am shooting a jacketed round after every cast round just to help clean out the gas system if that's an issue, but I really doubt much that it is with this particular bullet hardness (20-21 as it's for the .500 SW) and the fact that it's gas checked. I don't plan on shooting many of these as it's a large predator protection round and doing over 1475fps with 370g projectile is a noticeable wallop! That's the oomph of a .454 Casull but higher on the Taylor KO factor than .454 Casull. Fun to shoot though. Will report back with any updates.

[Moonie]

shooting jacketed after cast will not clean out the gas system. Cleaning lead and lube out of the gas system is not impossible, but it is very difficult.

[jmden]

Stopped shooting these as I noticed leading occuring near piston. Don't recall seeing this with the PC'd boolits. So the softer boolits ('cause boiled to get wax off and/or because of heating in oven from PC'ing) causes the infamous 'ring' OR using the un-PC'ed boolits, which are harder I think because they haven't been heated, well, those seem to be causing lead to go through the gas channel.

If I was to get some of these before the wax was applied so that I didn't have to boil all that off (probably greatly reducing the HBN in the process), how much does the 10min at 400F reduce HBN by itself? Is there a way to restore the orginal HBN after PC'ing?

[Silverboolit]

I am sure that you have thought of this, but..Is your case really headspacing in the barrel, or is the case being held by the extractor and leaving just a little of the chamber 'bare'? If it is being held by the extracter, this may be where the ring is coming from.

[jmden]

Well...I guess I'd need to get a chamber length plug (I do this for my bolt guns so I know exactly how long the chamber is so that I don't trim cases more than I need to) and see for sure. Probably a good thing to do although I don't think I've ever done that in a pistol.

Is that where you were going with that line of thought?

Sinclair does have one, although it's .510 so it might not work:

http://www.sinclairintl.com/reloading-equipment/measuring-tools/case-gauges-headspace-tools/sinclair-chamber-length-gage-prod32925.aspx

Thanks,

Jon

[jmden]

Any further thoughts?

[Silverboolit]

Pound cast of chamber? I would think that a pound cast should show total length of chamber.

[jmden]

Hmm... So what if this shows that my average case length (trimmed to spec nearly every reloading) is, say, .070 less than chamber length? That would seem to indicate to me a barrel that the reamer got run into a little too far...

[wonderwolf]

Hmm... So what if this shows that my average case length (trimmed to spec nearly every reloading) is, say, .070 less than chamber length? That would seem to indicate to me a barrel that the reamer got run into a little too far...

You're saying your cases are shrinking?

I'm trying to follow the thread of what the problem is exactly. You stopped shooting PC cast but your still wondering why you got a ring of lead in the chamber area?

I shoot a .44 DE and even though I cast I don't think twice about even trying any cast through it. I may swage my own bullets for it using .40 S&W as jackets but to be honest the gas system in a DE is just too hard to work on to even fuss with it. Although I get your motivation as .501 jacketed are not cheap.

[jmden]

You're saying your cases are shrinking?

I'm trying to follow the thread of what the problem is exactly. You stopped shooting PC cast but your still wondering why you got a ring of lead in the chamber area?

I shoot a .44 DE and even though I cast I don't think twice about even trying any cast through it. I may swage my own bullets for it using .40 S&W as jackets but to be honest the gas system in a DE is just too hard to work on to even fuss with it. Although I get your motivation as .501 jacketed are not cheap.

Yeah, the whole thing may be a moot point, just shoot jacketed and don't look back, but I'm just wondering if the issues I was having with the 'rings' were somehow related to greatly lowering the hardness of the cast bullets through heating.

What I'm trying to find out is basically is there a way to PC the cast bullets without lowering the hardness? When I shot a few out of the box hardcast bullets (without heating them while PC'ing) I had no 'ring' but could see that lead was going through the gas system. No good. When shooting PC'ed bullets, I had no leading issues, but had the 'ring'. I was shooting that 370g hardcast bullet at 1475fps, so pretty stout.