I currently use a load of 85gr of FF with a PRB in my GPR. I want to try FFF in the same flinter and was wondering what would be a good starting load using the FFF? Any suggestions? Should I start at my standard 85 or start lower becasue of the finer granulation of the FFF.
-
Friends, our 2nd Amendment rights are always under attack and the NRA has been a constant for decades in helping fight that fight.
We have partnered with the NRA to offer you a discount on membership and Muzzleloading Forum gets a small percentage too of each membership, so you are supporting both the NRA and us.
Use this link to sign up please; https://membership.nra.org/recruiters/join/XR045103
FF vs FFF in a .50 GPR Flint
- Thread starter dallas10c
- Start date
Help Support Muzzleloading Forum:
I would start lower, in my case I shoot 70 grains of 3F in my gpr. Another nice thing about using 3F, you can prime with the same powder. Only way I do it and I personally cannot tell the difference in ignition between 3F and 4F in the pan.
Walks with fire
54 Cal.
Recon,
You will get a bit more thump using 85gr. 3f vs. 2f but I think that barrel is rated to do up to 90 grains of 3f. Check out the Lyman site or your owners manual to be sure.
My GM barrel rates it up to 110 grains of 3f. I have done 100 and that more than enough. Most people with .50 cals. use up to 90. I just started getting into 3f because I was concerned with pressure but when I got the GM barrels I felt comfortable doing it. It's a huge improvement in my opinion; my longest barrel is 32" so I helps quite a bit.
You will get a bit more thump using 85gr. 3f vs. 2f but I think that barrel is rated to do up to 90 grains of 3f. Check out the Lyman site or your owners manual to be sure.
My GM barrel rates it up to 110 grains of 3f. I have done 100 and that more than enough. Most people with .50 cals. use up to 90. I just started getting into 3f because I was concerned with pressure but when I got the GM barrels I felt comfortable doing it. It's a huge improvement in my opinion; my longest barrel is 32" so I helps quite a bit.
Thanks for the info....I think I'll start with 70 and see how it performs. I wanted to try the 3f for the reason you stated. I can charge and prime with the same powder. I had to do that last time...but with 2f. It surprised me and went boom no problem.
Where in Tioga Cty are you?
Where in Tioga Cty are you?
What is the length of your barrel? That makes a difference on how much powder you can effectively burn. For instance, a 36" barrel in .50 cal. is maxed with aprx. an 80 grain load. This is based on the forumla of 11.5 grains of powder per every 1 cu. inch of barrel volume - there are discussions about this forumla in the forum.
- Joined
- Jul 4, 2007
- Messages
- 1,075
- Reaction score
- 85
Ah..tuna and noodles at the Wellsboro Diner. It is sublime.
BTW - I use 80grs. FFFg in my GPR.
Pete
BTW - I use 80grs. FFFg in my GPR.
Pete
If you're shooting 85 gr FFg try 80 gr FFFg and see if that don't shoot to the same point of impact. I have found, through trial and experiment, that FFFg has 6% more "oomph" than an equal volume of FFg in my flinter. And, not coincedentally, measured by volume and then weighed, FFFg weighs about 6% more than FFg of equal volume. FFg has larger granules and allows more air space between them, so it is less dense.
I use 3Fg for main and prime and it simplifies life immensely. I keep a little wood plugged brass tube to prime with in a loop on my horn strap and refill it from my horn as necessary. Simple.
I use 3Fg for main and prime and it simplifies life immensely. I keep a little wood plugged brass tube to prime with in a loop on my horn strap and refill it from my horn as necessary. Simple.
Recon said:
If anything but Swiss I would use 85-90gr of FFFG. I would back it off to 80 or so with Swiss.
I shoot FFFG in everything to at least 58. I shot FFG Swiss in the 66.
You will likely see an elevation change at 100 with FFFG.
Dan
paulvallandigham
Passed On
- Joined
- Jan 9, 2006
- Messages
- 17,537
- Reaction score
- 89
/recon: It all depends on the range you intend to shoot over, the weight of your gun, and the length of the barrel. I don't think more is better, so I can't recommend using more than 80 grains of FFg in your gun. The laws of physics say that any that goes faster, also slows faster. the faster you start that PRB out the muzzle the faster it loses velocity on the way to the target. I just don't think you get much real bang downrange for all that push at the muzzle. Here are some velocities for various powder charges out of the Hodgdon Reloading manual for .50 cal. PRB.
60 grs.FFg 1390 fps. ( nothing to sneeze at.)
70 grs. " 1554 fps.
80 grs. " 1729 fps.
90 grs. " 1872 fps.
100 grs." 1988 fps.
You can see the velocity begin to drop off as to increments per 10 grain powder increase, after 80 grains. But any load over 1500 fps is going some, and should penetrate a deer at 100 yds. If you look through the posts under the Hunting topic on this forum, there are lots of reports of .50 cal. PRB passing through deer with a 70 grain powder charge.
If FFFg is about 6% faster, take that into account to estimate your true MV using FFFg powder charges. I know that Swiss FFFg powder is a finer granule powder, and that the percentage of Potassium Nitrate to Sulphur is higher than is loaded in the States in Goex brand BP. So, if you use it, factor in 10% more velocity than these figures.
I recommend using FFg powder( Or Swiss 1 1/2g powder in all flintlocks, because the larger sized granules leave more oxygen around and in between each granule, speeding ignition of the main charge, and raising both the temperature and the chamber pressure faster than if you use FFFg powder. But, try them both in your gun. Some guns just shoot better using FFFg powder, even if they are flintlocks. When I find a guy with such a gun, I always want to take it home for my examination, and to tune the flintlock my way, to see if I can't better performance from the gun using FFg powder, but that is based on my years of learning to tune locks, and to make flintlocks shoot quickly. Not everyone is willing to take that time, or go to the trouble of having the lock really tuned. And, some shooters have just learned to hold their follow through longer than I think is normal for me. If it works, don't fix it. :thumbsup:
60 grs.FFg 1390 fps. ( nothing to sneeze at.)
70 grs. " 1554 fps.
80 grs. " 1729 fps.
90 grs. " 1872 fps.
100 grs." 1988 fps.
You can see the velocity begin to drop off as to increments per 10 grain powder increase, after 80 grains. But any load over 1500 fps is going some, and should penetrate a deer at 100 yds. If you look through the posts under the Hunting topic on this forum, there are lots of reports of .50 cal. PRB passing through deer with a 70 grain powder charge.
If FFFg is about 6% faster, take that into account to estimate your true MV using FFFg powder charges. I know that Swiss FFFg powder is a finer granule powder, and that the percentage of Potassium Nitrate to Sulphur is higher than is loaded in the States in Goex brand BP. So, if you use it, factor in 10% more velocity than these figures.
I recommend using FFg powder( Or Swiss 1 1/2g powder in all flintlocks, because the larger sized granules leave more oxygen around and in between each granule, speeding ignition of the main charge, and raising both the temperature and the chamber pressure faster than if you use FFFg powder. But, try them both in your gun. Some guns just shoot better using FFFg powder, even if they are flintlocks. When I find a guy with such a gun, I always want to take it home for my examination, and to tune the flintlock my way, to see if I can't better performance from the gun using FFg powder, but that is based on my years of learning to tune locks, and to make flintlocks shoot quickly. Not everyone is willing to take that time, or go to the trouble of having the lock really tuned. And, some shooters have just learned to hold their follow through longer than I think is normal for me. If it works, don't fix it. :thumbsup:
Thanks to all for the info and suggestions. I think I'll start at 70 and go up in increments of 5 till I see what shoots best. BTW..I always use Goex becasue it is all I can find around here in PA and it is relatively cheap $$ compared to some of the prices I hear people mention on the board.
Recon said:
Most rifles above 45 will shoot well with 1/2 ball weight +- of powder to about 58 cal. Above this less is needed. My .66 makes 1650 with a 1 oz (437 gr) ball and 110 gr of FFG Swiss. But it has a Nock breech and this may effect velocity. 1/2 ball weight in this rifle would be unbearable recoil wise if shot from any position but off hand and its stocked English style. Also the velocity increase would be very little, increasing from 110 to 140 gains only 100 fps. This rifle has a 30" barrel including the breech. 120 is probably the optimum load for velocity and minimized recoil.
However, it takes 90 gr of FFFG Swiss to get my 54 to just under 1900 and it has a 38" barrel. The bigger bores seem to use the powder more efficiently. Perhaps the shorter powder column lights faster??
The 54 has shot 3 shots under 6" at 200 with this load. The next 3 opened it to about 10". But a breeze came up while loading #4.
I had a Sharon Hawken (54x36" 72 twist) years ago that was happy at 120 gr of FFFG GOI/GOEX. Shot poorly with my normal 54 load of 100. Some shooters shot very heavy charges in small bores, some 40s, for example, shoot best with 50-60 grains according to the owners. Many people shoot 60-70 in 45s with a 130+- gr ball. The rifle will make the determination.
The advantage of the round ball is flat trajectory to 100-125 yards if loaded to the point where velocity increase per grain of increase falls off dramatically. Very short barrels, under 32-36" will show declines in increase sooner. To do well at this the 50-54 will need 85-100 gr of powder. Lower velocity will shorten the point blank.
The 66 will produce a trajectory that is within 3" of line of sight to about 130 yards. The 50-54 will shoot this flat to about 120. Meaning no need to change the hold on deer sized animals to this distance. If sighted dead on at 100 the rise above line of sight will be even lower. My 54 load if sighted dead on at 100 will only be about 1.9" high at 50. At 1500 it would be 3.1" at 50. This may seem minor but flat trajectories make hitting easier.
If a hunter does not need to shoot past 75 yards or has known ranges from a blind etc the lower velocity loads will work OK.
Since some in the industry are pushing for minimum energy levels for MLs used for hunting (so as to sell more conical bullets) it is interesting to note that the .662 ball at 1700fps exceeds 1000 fpe at 100 yards. 1600 makes 998 fpe at 100. The 1700 load makes 2800 at the muzzle. But ME is a very poor way to judge killing power. A 55 gr .223 load will be very close to the 66 cal's 100 yard energy level but the load is not in the same class with the .662" rb for shooting animals larger than perhaps a coyote.
Dan
Ok, I am kornfused. I have a 36 inch 50 cal 1 x 48 twist flinter. Some say 2F is better for flinters, because the "loose" larger granulations provides for better ignition. Then there is those who use 3F whatever the cal. Now I can go and do my own tests, but there should be some guidelines based on real experience that could save me some time and effort. I don't believe that each gun is its own animal. Either 2F or 3F should be best in a rifle of my given specifications. I just don't accept "it depends on your gun". I have 30+ years testing hardware/software professionally and so I expect to be able to get repeatable reliable results. So I will go an do my own tests, but it should be a hard fact what granulation of bp should be best. Just my humble opinion.
