Author Topic: .54 Great Plains Hunter - accuracy with heavy bullets (Read 1125 times)

Rum River · « **on:** August 24, 2004, 07:10:29 AM »

Tried it out over the weekend, hoping for better accuracy.

This rifle has the 32 inch barrel with the 32 inch twist. Tried T/C 430gr Maxi-Hunters and Hornady 460gr Great Plains hollow-base using Goex FFg. Best 100 yard group was at least 8 inches. Rifle has the Lyman tang rear peep, don't have the front aperture sight installed yet.

Swabbed the bore as often as every 2 shots, and as seldom as 8 shots. Other than the bullet being harder to seat when swabbing less often, there was no difference.

I started the powder charges at 80grs (volume) to adjust the sights. This rifle will be used in grizzly country in Alaska, so tried charges of 100, 110 and 120grs (volume) with no real difference between any of them.

The 50 yard groups were 2 inches, but want to find a way to get that kind of performance at 100 yards. I'll try a 90gr powder charge to cover all the bases, although I'd like to have all the knockdown power I can.

My wife and I will be hunting caribou, and I know I don't need this much horsepower for caribou. However, I might just need this much horsepower if a bear shows up.

Is it perhaps a deal where I need the 28 inch twist for bullets this heavy? Maybe the lighter bullets would work better in my 32 inch twist?

If that's the option, I might buy a Green Mountain with whatever twist I need to stabilize the big projectiles. I've seen load data for bullets up to the 530gr weight, but haven't found any of these in the stores so I can try them.

Any feedback appreciated.

quickdtoo · « **Reply #1 on:** August 24, 2004, 07:47:57 AM »

Precision Bullet has a chart to determine which of their bullets work with different twist rates, may be of some help.

http://www.prbullet.com/chart.htm

lostid · « **Reply #2 on:** August 24, 2004, 04:49:54 PM »

Be aware that the chart offered by Precision Bullet is designed for saboted rounds and bullet diameter only.
Your .54 will not shoot .54 cal bullets using a sabot. Precision Bullet will offer for your .54 a series of sabot style bullets in .44,.45 and 50 for your .54.

Now, depending on your guide and circumstance for Caribu,distance and accuracy, not knock down power is best, Caribo are wimpy, they ain't moose or bear, they have a light frame over the vitals and tend too bleed out quickly with proper placement.

When hunting different big game, one should study "end ballistics" of different projectiles,,,,,,,,,,,,big, long, is not always good.

If you want 2" 100yrd accuracy from a .54, something in the range of 300 to 380 is proven to be best. The object is to deliver and expend the energy of the projectile on contact with the target/game.

A 430grn bullet flying sideways and begining to tumble at 100yrds,cain't do as much too game as a prb that will "thunk" push and tear the "boiler room".

quickdtoo · « **Reply #3 on:** August 24, 2004, 05:40:33 PM »

The conicals are at the bottom of the chart under Conicals. :grin: They have 2 styles of conicals in .54 cal weighing from 400 gr to 535 gr.

http://www.prbullet.com/ul54.htm

Winter Hawk · « **Reply #4 on:** August 27, 2004, 07:43:24 AM »

I sold my .50 cal flinter and bought a .54 cal. GPR strictly because I wanted to use round ball and Alaska requires .54 minimum for that. I would not hesitate to use it on a big bear if the need arose.

You probably won't see a bear, if you do it will probably be at a long distance, and if he is close and charges it is probably going to be a bluff. By the time you determine that it is not a bluff it won't matter much if you have round ball or conical, you'll be wishing you had a .458 magnum! A wounded bear could just REALLy get mad at you!

I helped skin out a BIG blackie up north of here many years ago. The hunter used a 12 ga. with slugs, and it took five shots in the chest to kill that bear. Even with conicals I don't think your .54 will deter an angry grizzly.

My advice is if you are going to worry about bears then cancel the hunt. If you are going on the hunt don't worry about the bears.

my 2 cents worth...
-WH-

Rum River · « **Reply #5 on:** September 29, 2004, 05:27:55 PM »

Finally had a chance to do more testing.

As a previous poster stated, the lighter bullet weight made the difference.
The best performer is the T/C 365gr. Maxi-Ball with 120grs FFg Goex. From a clean, dry bore six shots without swabbing made a 3 1/2" group at 100 yards.

I'm happy.