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Hoyt GPR .54, 1:66 load recommendations

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Just received a .54, 1:66” GPR barrel re-bored by Bobby Hoyt (had been a .50). If you have had Mr. Hoyt do similar work for you, I am interested to know what hunting loads you have worked up in your Hoyt barrels?
 
No one can tell you what load your gun is going to like. Too many variables.
Start with a .005” undersize ball, .018 to .020 patch, and maybe 10g over your bore size, and go from there.
Youll find one that works pretty quickly.
So .535” ball, .020” patch, 65g of powder. Go up by 5g, till you find the smallest group. There ya are!
 
Measure your bore before you contemplate a ball that is 0.005 to 0.010 under the land to land bore diameter. Then it's a patch thickness that compresses to equal the groove depth and the difference between ball diameter and land to land diameter. Select a patch lubricant such as 1 part water soluble oil (Ballistol or any water soluble oil) to 7 parts water either as a dry patch or as a slight dampening of the patch. I favor real black powder to the substitutes but a charge can be developed for percussion locks using either.
 
Just received a .54, 1:66” GPR barrel re-bored by Bobby Hoyt (had been a .50). If you have had Mr. Hoyt do similar work for you, I am interested to know what hunting loads you have worked up in your Hoyt barrels?
Did you get his radius bottom rifling? Have two of his 58 caliber 1-60 rebores with radius bottom rifling and use a relatively thick patch to fill the grooves. Find that .023/.024” canvas that compresses to .016/.017” or so works well. Your ball diameter plus compressed patch material has to fill the rifling for best performance/accuracy in my opinion.

As far as powder charge, use 80 to 90 grain charges of 3F Swiss for my 58 and 54 caliber guns. It just works.
 
SDSmlf, yes, it’s a deep radiused groove. I fired it today and will use a little thicker patching next time.
I was grouping pretty well with 85 gr. 2f. Thanks for your answer.
 
Look SDSmlf, yes, it’s a deep radiused groove. I fired it today and will use a little thicker patching next time.
I was grouping pretty well with 85 gr. 2f. Thanks for your answer.
It’s not just thicker patching, it tight weave patching that doesn’t compress too much. With the narrow lands (at least in my 58 caliber Hoyts) it loads relatively easily. When the shooting gods are happy and the lighting is right (so I can see the sights and target properly), I can get 5 shot 100 yard groups right at 1”. Doesn’t always happen, but that’s on me, not the barrel.
 
Measure your bore before you contemplate a ball that is 0.005 to 0.010 under the land to land bore diameter. Then it's a patch thickness that compresses to equal the groove depth and the difference between ball diameter and land to land diameter. Select a patch lubricant such as 1 part water soluble oil (Ballistol or any water soluble oil) to 7 parts water either as a dry patch or as a slight dampening of the patch. I favor real black powder to the substitutes but a charge can be developed for percussion locks using either.
Are you saying have a 490 ball (for 50 caliber) and a .10 patch? Or a 495 ball and a .05 patch? Just asking I didn't know this. Thanks
 
Wrong forum. Neither make traditional products.
Well obviously it was a joke, but I would put dollars to donuts that there is a gentleman out there named Matthews that makes muzzleloader rifles as obviously there is a gentleman named Hoyt who makes muzzleloader rifles. I think it would make a great and iconic rivalry if Matthews was a great builder as well. Completely on subject for this forum.
 
Well obviously it was a joke, but I would put dollars to donuts that there is a gentleman out there named Matthews that makes muzzleloader rifles as obviously there is a gentleman named Hoyt who makes muzzleloader rifles. I think it would make a great and iconic rivalry if Matthews was a great builder as well. Completely on subject for this forum.
Pitiful waste of sarcasm on my part, my apologies for not being clear enough for you to recognize it for what it was. And if you believe it to be such a great topic, why not research it yourself? Would love to hear what you discover……
 
Are you saying have a 490 ball (for 50 caliber) and a .10 patch? Or a 495 ball and a .05 patch? Just asking I didn't know this. Thanks
If you have a land-to-land bore diameter of 0.500" and a groove depth of 0.012", you may want to select a ball of 0.490" with a patch that compresses to 0.017" (0.012+0.005) or 0.495" ball and a patch that compresses to 0.015" (0.012+0.003). I have found that using a patch that compresses to the groove depth + half the difference between the ball and the bore provides the best on target accuracy. Patches less than the groove depth will shred which isn't best for accuracy.
 
That’s what I thought…
Yet, even though they follow some generally accepted rules, every rifle is a law unto itself. I have a couple of Hoyt 58’s and they like thick patch and relatively heavy charges, 90-120 grains. Both received the shaver break in treatment and they don’t foul badly with good powder, (Swiss 2f or 1-1/2f) and clean easily.
 
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