maximum load size...

[Dave Rosenthal]

Paul,

I just ran the numbers for my .50 cal., 70 grain charge that I use in my Lyman trade rifles and the formula yields a result of 63.22 grains for a 28 inch barrel if I'm reading you right. This might help explain why this gun likes this charge as a "sweet spot" with both PRB's and the 370 gr. T/C Maxi-Balls I use to win competitions with.

Now here's one for splitting hairs:

Not that I or anyone else would, BUT what if I were to switch to 4F Goex? Would the faster burning powder be completely consumed in a 70 grain charge? Would the gun be over-stressed by too much pressure in the breech? Could the bore burn more than 63.22 grains mentioned above?

Does the formula you have cover just 2F? Reason that I ask is that I can shoot more than a whole box of 20 Maxi's before I even have to think about giving the bore a wipe or a brush. As stated before I'm using 3F now.

Just a hunch, but my guess would be that I might be over-stressing the gun with a 4F charge, but the velocity would go up and all 70 gr. of the powder would burn. What say you, Paul?

Thanks for the formula, your friend,

Dave

 

[Rebel]

The velocity would go up, the pressure would go up, and the gun MIGHT go up too.

 

[Dave Rosenthal]

:rotf: :rotf: :rotf: that's a good one,

DAVE

 

[PreglerD]

In GE we have a gunproofing law. This law rules that any firearm which will be traded on the GE market has to be proofed by the gun proofing institution. For all calibers both ML and modern arms there is a list with tested maximum loads and bullets.After 3 proofing shots the gun is marked by the institution. For example: in a cal. 45 ML rifle you can use a max. load bp of 92.4 grs with a 246,4 grs conical bullet.For cal. .54 you can use a max. load of 138.6 grs bp and a 431.2 grs conical bullet.The data are valid for longarms and shortarms. The proofing signs of some other countries are accepted, for example Italy (Investarm) and Spain (Traditions).

 

[Steve A.]

Alright! My math may not be so hopeless after all :shocked2: . I don't have a problem with that range. As long as it's enough powder to get the job done on deer under 75 yards i'm good to go. My longest shot was probly around 50 yards. Most of them have been under 20. (with modern centerfire rifles I still haven't taken one with a muzzleloader yet here's hopin :thumbsup: )

Actually i got out to do some shooting last weekedend,trying to work up a load ,and i found 70 grains 3f to be pretty acurate(probly more acurate than i am at the moment) at 50 yards. So that works out pretty good i say.

Zonie if ya wanna get real technical it's 72.193968 :grin:

Blizzard i don't have a 30-06 ,but i have plenty of 303 british laying around.They shouldn't be too far off ya think? I'll try measuring it out later. I'm glad to hear that charge works for you. Now i can be confident that that load will get the job done cleanly.

 

[roundball]

I don't think you have a worry in the world about all 70grns of Goex 2F or 3F burning up...

 

[paulvallandigham]

Smoke: You don't want to be putting priming powder down the barrel, unless its a few grains to shoot a dry ball out! Its not that modern guns are not designed to withstand rediculous pressures, and protect the company form product's Liability lawsuit that actually are the result of fool hardy screw ups of the buying public. The guns are generally strong enough.

I don't think most shoulder are strong enough to take that kind of diet. Besides bruises, you could dislocate a shoulder shooting 4Fg powder.

On some older guns, something might come apart, however, and injure the shooter or someone standing nearby.

The formula came from the head of Naval Ordinance, who was a long time member of the NMLRA. I am told he used to walk the firing line at Friendship, with his " book", and tell shooters what their best loads would be. He was generally right. The loads he recommended were below the maximum using his formula, but I have not been told how he came up with those less than maximum recommendations. He was always calculating in his " book ", but was very free with his advice.

As Roundball observes, you are not going to have much trouble getting 70 grains of FFg or even FFFg powder to burn in that short barrel. 28 inches sounds long compared to a modern rifle barrel, but in ML terms, its rather short. If you will use a chronograph to test your loads and back down to about 55 grains and work up in 5 grain increments, You will see where adding more powder, while producing more velocity, begins to add LESS velocity for every 5 grains more powder you add. Putting on a grand light show out the muzzle of your barrel may thrill the people watching you shoot, but it will add little to the velocity of your load.

The short barreled gun was intended for off-hand shooting at close range. In my 39 inch barrel .50 caliber rifle, I fired both a target load of 60 grains of FFg powder to test penetration of the ball at that lower velocity- I did not own my chronograph at the time- and then increased the powder charge to 100 grains, to see just how much more penetration I would get. What I got was a lot of unburned powder, and clinkers, on the paper I put on the ground in front of the muzzle- I tested the residue by putting it in a shallow dish, and lighting it- and the ball penetrated the SAME distance into my test medium ( 1 inch pine boards, spaced 1 inch apart) as had the target load. The recoil, however, was noticable.

Subsequently, I worked on a " 100 yd. Hunting load ", and found I get the best accuracy, with improved trajectory using 75 grains of FFg powder. That load is under my maximum burning charge of 88 grains. I could get more velocity putting in more powder, but not better accuracy, and not enough difference in the Mid-range trajectory to make any real difference, considering I was using open sights.

Most deer are shot at under 50 yards. At that range, a 28 inch barrel is not going to handicap the hunter very much, using a .50 caliber RB. The shorter barrel helps new comers to the sport of BP hunting adjust better to the difference between carrying a ML rifle, and a modern rifle. Once they gain confidence in the ML rilfe system, they become interested in owning and hunting with something with a bit more barrel length.

 

[Blizzard of '93]

If you know a handloader that has a scale weigh a .303 Brit caseful and see what you come up with. Any gunshop probably has empty '06 brass around, you might ask for a case. Real handy measure. Groups open up if I shoot any heavier charge than that - and I use a felt wad overpowder also. This is using a PRB, I just bought a Lee REAL slug mold so need to cast some and give them a try. Hopefully they will extend my 'killing range' some vs. the PRB.

 

[renovato]

Paul, many years back I had heard about unburned powder being the indicator of the max load. At the time, I couldn't understand how powder grains could not ignite under all that pressure and heat. Until I tried the very thing you mentioned, about gathering the grains and touching a match to the small pile and it flashed. I've since had others argue against this, and I've told them to try it for themselves. I think with some folks, like myself, seeing it is the only way to believe it.

 

[paulvallandigham]

Plink. That is how I arrived at doing that test, too. I was a total sceptic, but was with a buddy when I did the test. He said what was on the paper was unburned powder, but I thought it was just clinkers. He made me pick up the paper and pour the stuff into a pan, so he would not be accused of slipping some powder. He even made me light the stuff, then stood back and laughed when I jumped away from the burning powder! I did it one more time, and decided I had tested the thesis enough. It was unburned powder, as well as clinkers on the paper.

I have known only one other sceptic who was willing to go out and do the same test at my club. He was also shocked to find out there was unburned powder on the paper. He decided not to change his load ! He's not a good shot, does not come out and practice much, and is not willing to invest any effort in becoming a better shot. I don't know if he hunts, still, but I really hope he doesn't. If he actually killed a deer, it would be by accident.

 

[Dave Rosenthal]

Paul,

I didn't get a chance to do the "sheet" test you spoke of. Don't know if I'll ever have the time this season (Wedding Photog), so I'll just take your word for it...you haven't given me a bum steer yet :thumbsup: .

I did in fact get to "Chrono" two loads. The first was a regular 370 gr. Maxi-Ball by T/C, in front of 70 gr. of 3F Goex. At 1349 FPS, that's a power factor of 499, roughly that of a 20 ga. rifled slug used to harvest many a Jersey whitetail . The second loading is not a reccomended load by any means, but if I want to show-off a little with lots of fire & smoke, and completely destroy an evil watermelon, R. Lee Ermey style, I use a 470 gr. T/C Maxi-Hunter hollow point in front of 100 gr. 3F :shocked2: . Only a 6-inch piece of rind was left the last time I tried this :haha: , but the shoulder only takes ONE, then there's no :bull: around about the power of a ML . Not even a belt of .30 cal. machine gun can chew-up a watermelon like one good .50 cal. traveling at 1389 FPS. Doing the math, I figured it to be about the same as a 12 ga., 1 ounce rifled slug that's a little less weight but moving a little faster :shocked2: .

Come to think of it, I don't ever remember hearing about someone getting hit with a huge 650 gr. BMG bullet and getting back up and saying that the shooter didn't use enough gun! That the .50 cal. was too small for this or that! PRB's are one thing, but throwing more than an ounce of lead down range in a hurry is another! Wait a minute, that was on another thread :blah: .

It's almost Watermelon Hunting Season again. Last August, one of the District BSA Directors brought a watermelon with her to Summer Camp and gave it to me for our Troop, with the proviso that it NOT be used for the great DEMO :rotf: .

Your :youcrazy: watermelon assassin,

Dave

 

[paulvallandigham]

DAve: If you look up loading data for either the .45-70 or the .50-70 cartridges, I think you will find that your loads are pushing even those. Standard velocity rating for a current .405 grain .45-70 load is about 1200 fps. The .50-70 can be loaded with a cast 450 grain, or heavier bullet, and it will move through houses. The U.S. Army ordinance report on the Springfield Trapdoor rifles has a report of an fight with Indians where one bullet killed three Indians as they were lined up in a row as they charged the Cavalry's position. I really don't think you need to be pushing that heavy slug with 100 grains of powder.

i always caution people to keep ML shooting in perspective. The largest Sharps cartridge made( after market, and never by Sharps) was the .50-140-550 Sharps round. That was from a breechloading single shot rifle, with a very strong breechblock, a brass casing that could talk much of the chamber pressure by itself, and an early " steel " barrel. The replicas made today are much stronger, because the alloys used are so much better, and the metallurgy is so much improved. The cartridge has a tremendous recoil, and the stock needs to be inletted correctly and bedded correctly to keep it from cracking at the wrist, and tang areas. What it does to your shoulder depends on the shooter, how he holds it, how much he weighs, and what kind of buttplate is on the gun.

If you want to fire rip-snorting BP ammo, get a BP cartridge gun and the margin of safety they provide.

If you want to handicap your hunting, so you are required to get in close, use open sights, instead of a scope, have to pick your shot placement in order to make a clean quick kill, then shoot a ML with BP and a PRB. If you are hunting Elk, or Moose, or Caribou, or large bear, and even large wild boar, you want to consider using a conical. Just remember that the distance at which you will be shooting tend to be shorter than longer, and while the ball or conical can kill at many times the distance, its your ability to use open sights accurately that determines when you take a shot, if you take one at all.

I have concocted some " Rhino Rolling " loads for my .45-70 that shoot flat to 200 yds., but I would never try to load enough BP in my muzzle loading rifle to attempt to equal those velocities. Its not that the barrel might blow up. I am afraid of the stock failing, and my shoulder taking a year's medical leave! :shocked2: :rotf:

 

[Dave Rosenthal]

O-K Paul, I admit I might need to tone-down the watermelon destroyer load :bow: . I'll get some practice in later this month or next with a couple of test melons with a smaller charge :redface: .

As far as the 370 gr. Maxi in front of 70 gr. of 3F, I think that I'll stick with it as it is very accurate, even on windy days, and often leads to a win at the league competition. A complete match, including sighters, is just a box of 20 conicals. My shoulder is still O-K. Sometimes I even go to my Trap Club AFTER I shoot the BP league. After another 100 rds. of 12 ga., I start to feel the need to stop.

I recently bought a .45-70 H&R break-open single shot rifle called the "Buffalo Classic" or something similar. Used the Goex 405 gr. RNFP BP loads from Cabela's. Compared to a 12 ga. Max Dram 1 ounce slug, the .45-70 was a wimp load as far as recoil goes. The .50-90 or something like that would probably be right up my alley.

Thanks for your help,

Dave

 

[paulvallandigham]

Dave: Load that .45-70 with smokeless powder to the same velocity and you won't call it a wimp load. Only because you are shooting black powder is that recoil tolerable. More of a rolling punch, than a sharp crack. The loads I was talking about use 300-330 grain bullets moving along at 2000 fps. They also get your attention, but you can hang on to the gun. My Marlin weighs about 8 lbs. which is about 2 lbs more than that break open rifle you have. Stick with those BP loads in that rifle. That extra weight does make a difference.

 

[Blizzard of '93]

Paul do you have any experience with shooting the Lee REAL conical slug? I'm wondering what to expect with it. I have a .50 cal. 24" barrel. 1-48 twist. 320 gr slug. Have been using 3F powder. Will be some time before I can make it to the range.

 

[paulvallandigham]

NO, I odn't have any experience with the Lee Real bullet. I have heard more good things about it than bad, however.

My .50 cal rifle has a very thin barrel, and was never intended to be used with anything other than a PRB. I have the parts for a .50 hawken rifle, with a much thicker barrel. If that ever gets built, I will probably try out the conicals in that. Then, I too will be looking around to find someone with a Real bullets so I can try a few. The nicest thing about them is that they shoot well out of slow twist barrels, designed for shooting round ball instead.