Lyman Great Plains Rifle- 20 years later

[Palladan44]

Have had my good old Lyman GPR caliber 50 Cap lock for over 20 years now. Built her from a kit purchased at Sportsmans Warehouse.
(that location is now a big chain church of some type, and where the gun counter was is now an alter)
My mentor, a guy named Niki or Nicky worked the counters back there, and he set me up with the kit, and all the basic supplies and accessories i needed to succeed. Back then the kit cost between 250-300$ if I recall correctly.

The store didnt sell real black powder, but had plenty of BP subsitutes. So 777, Pyrodex, and Jim Shockeys are 3 types ive used over the years. Ive settled on 777 in FFF.
Nicky said FF might not ignite as good, so just use FFF and should be fine. I was in no position to contest, so FFF has been what i go for, no questions asked....(feel free to comment)

I use between 70 and 90 grains of 777 FFF under .490 round ball patched with .015 bore butter lubed patches. Greatest accuracy comes with 70 grains, where im of the assumption that 90 grains is probably better than 70-80gr for deer hunting, and groupings only open up ever so slightly with the extra powder. This is just what i was taught/told, and it has worked at killing deer (4 deer in about 20 years, 5 shots fired...one was a total miss, didnt even graze him)
Say 3" at 50 yds with 90grn bench rested rather than 2.5" with 70 grns.
Anybody have any clue what kind of velocities this is creating? Where is the envelope in this situation? Ive started getting worse groups, and torn up patches around 95grn or above, so thats where I quit and backed down.

 

[paul harm]

The only thing I've ever used is real BP so I can't comment on your powder selections. I started with TC Hawkens and went to my own rifles. 95 grains of 2F never presented a problem. About the same loads in my Bill Large 50 or 54 cal barrels all gave great accuracy. I never gave velocities a second thought. Good groups and they killed many a deer. Couldn't ask for any more.

 

[Hugger-4641]

I'm just few weeks away from getting out my Traditions .50 cal. I also use Pyrodex and 777 FFF, but I'm using 100grs with a 250gr sabot. I didn't have a chrono last year, so I'm curious myself, but I'm expecting 1500 to 1700fps or so. I'll post it when I do it.

 

[Thomasss]

I knew Nikki too and it was "Nikki." FPS in a .50 cal. will depend on the maker of the gun, the length of barrel and the powder mfr., you said 777, 3F. At 70 grains you could be as low as 1,300 fps and at 90 grains you might be in the 1800 fps neighborhood based on published load data. Again, more info would be helpful. The difference between FF and FFF powder is FF is a little slower but develops more bullet energy in some guns. It may be more accurate in some, too. But as you might have found out some guns like certain powders. You also need to remember 777 is 15% stronger than Goex or Pyrodex. Keep that in mind if you load maximum.

 

[rodwha]

Have had my good old Lyman GPR caliber 50 Cap lock for over 20 years now. Built her from a kit purchased at Sportsmans Warehouse.
(that location is now a big chain church of some type, and where the gun counter was is now an alter)
My mentor, a guy named Niki or Nicky worked the counters back there, and he set me up with the kit, and all the basic supplies and accessories i needed to succeed. Back then the kit cost between 250-300$ if I recall correctly.

The store didnt sell real black powder, but had plenty of BP subsitutes. So 777, Pyrodex, and Jim Shockeys are 3 types ive used over the years. Ive settled on 777 in FFF.
Nicky said FF might not ignite as good, so just use FFF and should be fine. I was in no position to contest, so FFF has been what i go for, no questions asked....(feel free to comment)

I use between 70 and 90 grains of 777 FFF under .490 round ball patched with .015 bore butter lubed patches. Greatest accuracy comes with 70 grains, where im of the assumption that 90 grains is probably better than 70-80gr for deer hunting, and groupings only open up ever so slightly with the extra powder. This is just what i was taught/told, and it has worked at killing deer (4 deer in about 20 years, 5 shots fired...one was a total miss, didnt even graze him)
Say 3" at 50 yds with 90grn bench rested rather than 2.5" with 70 grns.
Anybody have any clue what kind of velocities this is creating? Where is the envelope in this situation? Ive started getting worse groups, and torn up patches around 95grn or above, so thats where I quit and backed down.

Hodgdon’s site posts some data. For a patched ball they just show figures for 2F. The rule of thumb is that it takes 10% less 3F to achieve 3F results. So their 80 grn charge of 2F should equate to 72 grns of their 3F, which produced 1842 FPS. I, too, have a .50 cal Lyman (Deerstalker) and use energetic 3F powder and have broken it in with 70 grn charges so I just reduced the velocity to 1825 FPS and 1309 ft/lbs and called it good. At 100 yds it still has 441 ft/lbs. Using their 100 grn charge data to replicate a 90 grn charge we see a velocity of 1988 FPS with 1554 ft/lbs. But at 100 yds it’s down to 498 ft/lbs. So we see that at 100 yds where the killing is often done there’s not really a difference. At 125 yds, having been zeroed at 100, is -3.7” and -3.2” for me at 900’ elevation.

https://hodgdon.com/wp-content/uploads/2017/01/muzzleloading_manual_2008.pdf

 

[rodwha]

I knew Nikki too and it was "Nikki." FPS in a .50 cal. will depend on the maker of the gun, the length of barrel and the powder mfr., you said 777, 3F. At 70 grains you could be as low as 1,300 fps and at 90 grains you might be in the 1800 fps neighborhood based on published load data. Again, more info would be helpful. The difference between FF and FFF powder is FF is a little slower but develops more bullet energy in some guns. It may be more accurate in some, too. But as you might have found out some guns like certain powders. You also need to remember 777 is 15% stronger than Goex or Pyrodex. Keep that in mind if you load maximum.

The 15% reduction was merely to achieve lesser powder velocities, not safety. Triple 7 is slightly less potent than Swiss and Olde Eynsford in handgun side by side tests (haven’t seen anything for rifles).

 

[ThomasT]

Anybody have any clue what kind of velocities this is creating? Where is the envelope in this situation? Ive started getting worse groups, and torn up patches around 95grn or above, so thats where I quit and backed down.

Your patches are more likely burning up than tearing. Next time you go shooting try this. Add your powder then instead of the patched ball use one patch just barely inserted in the bore then your patched ball on top of that and ram it down. The extra patch works like a firewall and takes the heat and saves the ball patch.

I do this any time I use more than 75grs of powder. Then I pick up my patches and look at them. The firewall patch is burned up but the ball patches look so good you could almost reuse them. Give it a try.

 

[Ugly Sauce]

My Jeager will look like it's tearing patches, with no wad, or a single wad under the ball. Two wads and the patch comes out perfect.

 

[Jackrabbit1957]

Sam Fadala suggests using the outer covering from a hornet nest on top of the powder. I tried it and it will keep the patch from burning. Problem is where I've moved to there's no hornets.

 

[rodwha]

I always read this as hornet’s nest. What comes to my mind are the various paper wasps that build nests under the overhangs and whatnot. What little I know of hornets seems to suggest they tend to live under ground. What exactly is “hornet’s nest?”

 

[Palladan44]

Big oval shaped hives sometimes 10-15" in size.
Usually 10-20' off the ground in trees.
Bald faced hornets and yellowjackets both make them.

 

[jdavis123]

Here you go Rodwah. If you ever see one be sure it’s unoccupied before you get too close. The hornets can be pretty vicious when disturbed.

 

[rodwha]

This is what our yellow jackets make.

 

[ThomasT]

I don't play well with wasp. Thanks but I will stick with just using a second patch under the ball.

 

[jdavis123]

Rodwha, if you tear into a hornet’s nest you will find a nest that looks like the one you posted. They just build a shelter around the nest.

 

[Thomasss]

2011 Hodgden Safety Sheet:
"Triple Seven is a high energy product designed to provide the muzzleloading hunter with higher velocities when used in the same VOLUME as blackpowder. To duplicate a blackpowder load velocity using Triple Seven, you must decrease the powder charge by 15%."
It's interesting that this information is no longer on Hodgden's website. I did check their published loads going all the way back to the early year 2000s and found them to be the same as the label of 777 I just bought last year. I might also add sometime after 2005, Hodgden dropped the wording "Black Powder Substitute" from the Pyrodex label and now I believe all their muzzle loading powders say "Muzzleloading Propellent." New shooters need to understand we all use a universal "volume" measurement equivalent to black powder. And many firearm manufacturers still say "black powder or Pyrodex equivalent" in their loading requirements.

 

[Ugly Sauce]

View attachment 1011995

This is what our yellow jackets make.

May I never meet a Texas yellow jacket.