Polymer Coated Bullets and Crimp Style

[El Sobrante Kid]

When using polymer coated bullets do you prefer a (light) roll crimp or a taper crimp? Currently I am using .38sp cases with polymer coated bullets from Eggleston, and trying different loads with American Select to find the best compromise of accuracy/recoil/clean burning. This is my first go-round with polymer coated bullets (yes I know, living in a cave, LOL). Doing some research I see conflicting comments about roll crimps scraping off the coating, taper crimps allowing the bullet to set back into the case, etc., etc. What is your experience, what type and how heavy a crimp do you use, and do you have a favorite crimping die that you find works better than anything else?   Oh... and do you find that trimming all the cases to the same length does or does not make much difference (for CAS loads)?  

 

ETA- What do you do if the polymer coated bullet you are using does NOT have a crimp groove? How does that change your crimping strategy?

 

Thank You Muchly,  The Kid

[Smokin Gator SASS #29736]

For semi auto calibers I taper crimp the same as traditional lead bullets. Revolver or rifle calibers roll crimp in the crimp groove.  There have been times in the past where to get the desired overall length to feed in a lever rifle I would roll crimp into the front driving band to load a little longer. This was with traditional non coated lead bullets. I don't know if doing the same would actually cause a problem with coated lead but it could crimp through the coating.

[Null N. Void]

Didn't change a thing when I went to polymer coated bullets without a crimp grove.  They are Scarlett's bullets 125 grain that I load into .357 cases.  No difference in performance. 

[El Sobrante Kid]

50 minutes ago, Null N. Void said:

Didn't change a thing when I went to polymer coated bullets without a crimp grove.  They are Scarlett's bullets 125 grain that I load into .357 cases.  No difference in performance. 

 

So do you roll or taper crimp? Light or heavy crimp?   Thx

[Flinthills Dawg]

El Sobrante Kid basically how ever you loaded lubed lead bullets, do the same with the coated ones. No need to change the crimping lighter or heavier.

[Krazy Kajun]

I roll crimp.  If there is a crimp groove I don't put a heavy crimp.  If there is no crimp groove I use a little heavier crimp since there is no ledge.  I use a Lee factory crimp die.

 

Kajun

[Null N. Void]

1 hour ago, El Sobrante Kid said:

 

So do you roll or taper crimp? Light or heavy crimp?   Thx

Medium roll crimp..

[The Original Lumpy Gritz]

I use a LEE Factory Crimp Die with no issues. 

[Bingo Montana]

I have used HI-TEK coated bullets from Cheycast with no issues with crimping both in and out of the crimp groove.  The engineer in me even went so to test the coating by recovering some coated 125's crimped outside the crimp groove to 1.485 OAL that I shot into the berm, the HI-TEK coating was still intact and had not separated in any way.  You can see the same result if you smash them with a hammer of the garage floor!  I load with APP 3FG and use what you might call a medium to heavy crimp.  I found this works best for my 38 SPL APP 3FG load, brass seals well in chamber and comes out pretty darn clean.  I like how clean the coated bullets load and after thousands of rounds, zero leading.

 

Good luck Pard!

[ShadowCatcher]

Revolver reloads get a roll crimp, semi-auto reloads get a taper crimp, irrespective of the bullets coating.

To me the biggest advantage of the coated bullets over plain lead is not having to handle the lead while reloading,

and maybe a bit less lead in the forcing cone or barrel.

 

SC

 

[Smokin Gator SASS #29736]

I have seen discussions that say over crimping can break through the coating and potentially cause a problem. I don't know if that's been shown to be true and might only be a problem pushing max velocities as opposed to common SASS loadings.

[Oak Ridge Regulator]

I shoot 45 colt with a 200g bullet and a reduced powder load and I roll crimp pretty heavy, I finally ran a Lewis lead remover through my barrels after more than 10K rounds and there was almost nothing to be removed, I would say the hitech coating is pretty tough stuff and crimping doesn’t seem to effect it much, your mileage may vary

[Lassy LaRock]

For Pistol Ammunition Taper Crimp.

For Revolver Ammunition Roll Crimp.

[Go West]

You do not need a crimp groove with lead bullets, coated or not.

If you loaded lubed bullets, you need not change a thing for poly coated bullets.

We have several lightning rifles that I load longer than with the supplied crimp groove if they have them.

Crimps are sufficient to keep bullets from collapsing into the case and to ease chambering in rifles.

[El Sobrante Kid]

Thanks everyone! I have always reloaded using a roll crimp for revolver and taper crimp for semi-auto, whether or not there was a crimp groove. But the warnings about scraping off the bullet coating had me wondering. I appreciate all the comments and you sharing your personal experiences. The Dillon is all set up to crank out the first test load with American Select. Thank You Again!

[Choctaw Jack]

A quality powdercoat should not be affected by crimping.

If your coating is damaged by crimping, then either the coating has failed or the process of coating wasn't right.

I cast and coat all of my own pistol caliber bullets, and they pass the "hammer and anvil test".

Of course,

YMMV.

Choctaw Jack 

 

 

[Eyesa Horg]

Only issue I've had with coated bullets, is in my Rugers. Since switching, my seating die never gets crudded up and the finished round is cleaner. 

The issue with both my 45colt NMV's is I'm getting a hard fouling for about 2 inches in the middle of a 4.62 barrel. Never had the issue with lead & lubed bullets. Whatever it is, does not budge to solvents or even discolor a patch. Run a brush thru and comes right out easy peasy! Haven't really done any investigating, but thinking maybe the chamber throats are to small and damaging the coating. No issue in the Marlins or Ellie's 38s

[Attica Jack #23953]

I think the only way to scrape the hi-tec coating off the bullet is that you didn't put enough flare on the brass case.  When I switched to coated bullets, I increased the flare just a bit.

[Eyesa Horg]

2 minutes ago, Attica Jack #23953 said:

I think the only way to scrape the hi-tec coating off the bullet is that you didn't put enough flare on the brass case.  When I switched to coated bullets, I increased the flare just a bit.

I can certainly try that. I would expect to see coating building up on the shell plate though if it was being scraped off by the brass. I'm just wondering if the bullets are getting swaged a little leaving the chamber throats allowing gas by and melting the coating in the barrel. Using Hy- Tech coated bullets.