Ballistic gelatin test results : Modified Hornady 85 grain XTP JHP (32 ACP)

[Brass Fetcher]

Projectiles fired were Hornady 85 grain XTP JHPs, trimmed down to 71 grains and 76 grains. This was done in the interest of finding an FBI-compliant load for the .32ACP 'mousegun'.

Firearm was 2.75" barrel Kel-Tec P32.

Block calibrated at 10.1cm and 588 ft/sec impact velocity.

71 grains

Shot 1 - 1.9 grains of N310 powder, WSPP. Bullet penetrated 12.6", average expanded diameter was 0.356". Shot impacted at 851 ft/sec.

Shot 2 - 2.0 grains of N310 powder, WSPP. Bullet penetrated 13.3", average expanded diameter was 0.379". Shot impacted at 872 ft/sec.

Shot 3 - Somehow walked out of the ammunition box amidst all of the excitement. It is probably doing its 'landmine' impression right now on the ground of the facility where the testing took place.

Shot 4 - 2.2 grains of N310 powder, WSPP. Bullet penetrated 13.3", average expanded diameter was 0.398". Shot impacted at 930 ft/sec.

Shot 5 - 2.3 grains of N310 powder, not fired at the block, but chronographed. (Primer was starting to flatten out). Velocity = 970 ft/sec.

76 grain bullets

Shot 1 - chronographed only, velocity = 828 ft/sec.

Shot 2 - 1.9 grains of N310 powder, WSPP. Bullet penetrated 13.1", average expanded diameter was 0.363". Shot impacted at 848 ft/sec.

Shot 3 - 2.0 grains of N310 powder, WSPP. Bullet penetrated 14.4", average expanded diameter was 0.360". Shot impacted at 922 ft/sec.

I cut the bullets down using a 5/16" collet to hold the bullet in the lathe and a standard carbide cutter tool. The feed rate was 0.2mm/rev. I found that coming in about 0.068" off of the rearward face of the bullet will take away enough material to transform a 85 grain XTP into a 71 grain XTP.

Here's pics of the block and bullets.

 

[Srigs]

Good information and thanks for sharing your findings!

 

[griz]

Did you machine off the base of the bullet? That's the way I understood the description, but it would seem that the core would squirt out of the jacket. I am probably misunderstanding something.

 

[Brass Fetcher]

I did machine off the base of the bullets. There was some concern that a problem could arise because of this (I have only seen exposed lead bases in a .380ACP Winchester Ranger bullet before, everything else has been jacketed at the base. That is why, for the first shot, I taped the pistol to a fence post and pulled the trigger with 550 cord.

 

[griz]

It isn't the first shot that would be the problem! But seriously, you obviously were aware of the possibility of a jacket getting stuck in the barrel and took precautions. Good enough for me.

Thanks for the report, Griz

 

[RyanM]

Corrected due to calibration, the results were

71 gr
1: 11.3"
2: 12.2"
4: 12.3"

76 gr
2: 11.8"
3: 13.0"

Still not too shabby.

 

[dev_null]

Decent penetration but not enough expansion to suit me, not to mention doubtful utility if it hits bone on the way in.

Thanks for this!

 

[Brass Fetcher]

RyanM, thanks for the correction info. I don't have my 'simplified procedure' handy, just the book and all the PDEs to work through...

JE223

 

[RyanM]

I actually use a completely different process than the simplified correction. Simplified correction is only accurate to +/- a bit if you're using heavy for caliber (.160 to .170 or so sectional density, or 109 to 116 gr for a .312" bullet) expanding hollowpoints at 800 to 1000 fps. Anything else, like shotgun pellets, FMJs, light bullets, fast bullets, etc., will be off by more, depending on how different the projectile is.

 

[Newton]

Looks to me like you have managed to create a better load for the P32 than any of the major manufacturers have previously managed.

This must have taken a lot of work and time on your part - bravo !!

 

[Brass Fetcher]

Looks to me like you have managed to create a better load for the P32 than any of the major manufacturers have previously managed.

This must have taken a lot of work and time on your part - bravo !!

Thanks Newton, that's really nice. Actually, the work part was in guessing/figuring the right weight to cut the bullets down to. I have shot every expanding point factory 32ACP that I know of through that gun and have pushed 60 grain XTPs to 1200 ft/sec in handloads (which was very much a white knuckle affair) as well. So I had an idea (and the help of RyanM, with regard to what weights will penetrate to what distance for a given diameter, etc.) for what weight to aim for.

I knew about the expansion of the 85 grain XTP when loaded in a .32NAA - so I figure, take the same hollowpoint cavity and make the bullet shootable in a .32ACP. The lowest expansion velocity for the 85 grain XTP in gelatin is 800 ft/sec - which is easily obtainable using a fast powder and pushing a 71 grain bullet in the .32ACP. This performance could be had by loading the 85 grains in a .32ACP, but the pressures would be dangerously high, IMO.

JE223

 

[Brass Fetcher]

I'm not sure what you want to compare with the Remington load...

But, I will say that there is a huge difference in velocity between short barrels (on actual guns made for concealment) and 4" test barrels. I like the N310 powder because its burning rate is among the fastest, which IMO makes it better for short barrels like 2.75" barrel on the P32.

It gets mentioned every so often that European factory loads for the .32ACP and .380ACP are usually hotter than the American loads. This is usually attributed to the existance of Jennings and Raven, etc, pistols and liability. I know that the Kel-Tec is modern and high quality, so handloading at and slightly above maximum is not a big concern for me. 'I rolls the dice, I takes my chances' in this regard, so the velocities are somewhat higher than the rounds you mentioned would likely go in the same pistol.