62 grain BTHP

[ghostly]

I'm fortunate, my 77 gr plinking load shoots 1/4" left of my hunting 70 gr TSX load.


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[darr3239]

Does everyone remember when Colts with fixed carry handles and HBARs were $1,600?

And now we get FF rails and flat tops for $750.

Inflation what?

HUH?

I get it now. You meant that post for the CDNN Colt Sporter thread.

[308sako]

Does everyone remember when Colts with fixed carry handles and HBARs were $1,600?

And now we get FF rails and flat tops for $750.

Inflation what?

I think what you are referring to is the derailed handguards, derailed like this thread has become?

[MisterHelix]

So I did a little 'amateur hour' fragmentation testing. If your a stickler for technical methodology, just ignore this post.

My backyard setup is a 16x8x8 cardboard box with four gallon ziplock bags full of water and a 6-ply cardboard backer. I put a gallon jug of water behind the whole deal to catch deeper penetrating rounds.
I know, I know, it's not calibrated ballistics gelatin. What it is is repeatable, accessible, and cheap. I think it provides an adequate comparative look at the performance of various projectiles, though I'm not sure how well it relates to actual terminal performance. It creates a 16" water column, with intermittent layers of skin-like membrane.

Anyway, the 62 HPBT, at MV 2,745, performed like so:

Total penetration = 15" (four bags, dented cardboard backing, core did not exit bag 4, but poked a hole)
Recovered weight = 44 grains
Fragment dispersion = most of lead core in bag 4, most of copper jacket in bag 3
Damage path = bag 1 pierced, bag 2 shredded, bag 3 torn badly, bag 4 pierced.

For comparitive purposes, a 77 nosler cc went through all four bags and deposited 75 grains retained weight, with the lead core in the back-up jug and the jacket in bag 4.

A 50 grain OTM blew the front of the box off, turned bag 1 into confetti, and deposited a 25 grain bit into bag 3, which was barely damaged save for a tidy entry hole.

So, (obviously) less penetration than the 77, better performance than the varmint round. Not that surprising.

Make of it what you will.

YMMV.

(Edit: load data and group size: 62BTHP/BM@23.4gn/CCI450/LC mixed date brass/Lee FCD/OAL=2.245". MV = 2,745 from 16" SR15mod2, 1.25" at 100y with TR24g 4x, green triangle reticle) loaded on hornady LNL AP progressive.

[markm]

Did the 77 frag? When I've shot them into water jugs, they frag like crazy.

[MisterHelix]

Did the 77 frag? When I've shot them into water jugs, they frag like crazy.

After checking my notes, I see that the 77 nosler was only going about 2450 fps, from a 12.5" noveske, so, not the best comparison. I'm sure that had an influence on the projectile's behavior. But no, in that instance the 77 did not frag (much), mostly just losing its jacket and penetrating about 18". The lead core was quite deformed and flattened, but held together (mostly).

Edit: here's a better comparitive baseline. I went and put a round of Speer GDHP 64 grain over the Chrono, and through the water column.


64 GDHP at MV 2,786 performed like so:

Total penetration = 16" (four bags, severely dented cardboard backing, bullet did not exit bag 4, but poked a hole)
Recovered weight = 61 grains
Fragment dispersion = single, mushroomed projectile in bottom of bag 4
Damage path = bag 1 pierced, bag 2 torn badly, bag 3 torn badly, bag 4 pierced.

Attachment 48251

[308sako]

I have shot several coyotes with the 62 BTHP so far and have found the performance to be as your bags might indicate. Not as explosive as a varmint bullet but capable of stopping them DRT.

[opngrnd]

Has anyone done a run of these with H322? I'd have thought Benchmark might be too fast, but since it works, maybe there's a good load for H322. I'd do it myself, but I shot my chronograph...

[ghostly]

Yes H322 will work great.


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[the_accuser]

Has anyone done a run of these with H322? I'd have thought Benchmark might be too fast, but since it works, maybe there's a good load for H322. I'd do it myself, but I shot my chronograph...

I'm using 23.1gr H322