Useing over size bullets

[Leatherman]

I have two new projects (rifles) I am getting to shoot after much work on getting forming dies made and making brass for. They are a double rifle hammer gun in 10.5 X 47R and a double rifle hammer Drilling in 9.5 X 47R over 20 gauge. As usual these two rifles were not the norm in case shape or bore size for their caliber so dies were not readily available from CH4D or anyone else. In researching these two calibers I found there were as many as 30 variations so you get what you get I guess. I have always read and been told that a lead bullet should be up to .003" over groove size of your rifle but since I have been playing with these German black powder cartridge guns the last few years I have come to find that they have exceptionally large throats and long leads. I have been concerned about having to work the brass so much necking it back to the bullet I picked for the bore. I have also had some leading issues on some of my rifles even though the bullet was .002" over . Well I have also heard guys on this forum and others say pick a bullet that fits in a fired case and shoot it! I checked a couple of my guns fired cases and measured the difference of the bullet I was useing and what the fired case would except and I had guns with .007" to .016" larger capacity which I felt was too much from what I had always read in loading manuals and articles written by so call experts who always said .003" max. Well I attended a shoot early this month where they were shooting a lot of different types of rifles and cartridges and found most were reloading right at the bench . They were decapping and priming , measuring the blackpowder and then hand pressing a lead bullet in the un sized fired brass. When I queastioned the lack of resizeing the necks they answered they used a bullet that fit the fired case as close as possibly so it was a snug fit by hand. No crimp was needed either. When I asked about the size of the bullet in relation to the bore they said it wasn't a concern as the old rifles throats were over sized and the leads long enough that the bullets swaged down upon fireing. These guys were not new to this and had been dong this for years with many types of rifles mostly vintage guns and all swore by it. So I came home and fire formed a case in each of my 47's and am now shooting a .429" (44 mag) bullet in my 10.5mm which has a .413" groove bore . Now I am looking into some of my other rifles to try larger bullets in, some have even larger differences in groove size and the fired case neck dimension. One is another double rifle based on the .450 BPE but necked down I thought to a .446 bore. I have never gotten it to shoot accurately useing .447" lubed bullets and paper patched bullets . The bore measures .446" but fired cases will accept a .458" bullet so I can use 45 caliber bullets and 45/70 dies to neck size and bullet seating. I am hopeing this is the answer to my problems with this rifle. Any one else have experience doing this method of reloading?

[sharps4590]

A couple things. First off you're working with BP and pressures are going to be fairly low. Secondly, all the BP rifles and cartridges I've worked with, save possibly one, (the jury is still out on it), have preferred a pretty soft alloy. Decades ago I settled on 25-1 as my "standard" for BP cartridges. At the pressure levels BP operates, the volume of the charge and the soft alloy I wouldn't be afraid of .010 over groove providing the rifle is in good condition and, as you mentioned, the throat is that "loose". I wouldn't do it with jacketed bullets even over black powder.

The leading issue has always left me bumfuzzled. I have never had a leading problem with BP and soft bullets. Perhaps I've been fortunate as I know others have experienced difficulties. Evidently I was again fortunate in that the dies from Dave at CH-4D were a near perfect fit for my 10.5 X 47R. For the bullet I acquired a mold from Tom at Accurate molds and the two I just mic'ed measured about .418 as cast. I would have to look up my data to see if I size them or shoot them unsized....can't remember that either. Weight is around 270 grs. and I forget the groove dia. of the rifle. They work fine in my rifle.

Mike and others have always said if the bullet you desire to use freely enters the mouth of a fired case you're probably good to go. I have found this to be true in my work with cast bullets whether using BP or smokeless.

My Haenel/Aydt Schuetzen rifle has the throat/groove relationship you talk about, a very loose throat as compared to groove diameter. I shoot smokeless in it so as the groove is .345 I shoot .347-.348 hard cast bullets over I think 16-17 grs. of SR-4759. I won't argue with the sub-MOA groups at 100 yards, benched. As it's a straight taper case working the neck isn't as hard on the brass as if it were a bottlenecked case. Rifles are strange critters sometimes.

[Diz]

Leatherman,

I have just the opposite problem in that everything I shoot has a tight bore and chamber but it would seem to me that the oversize bullet would not be a problem. I know of other shooters doing the same thing that you mentioned your fellow shooters were doing with fine results. A good friend is doing just that with a couple of old rolling blocks. Also from my own experience I find that soft lead is not the culprit with leading but the lube that is being used. I have been experimenting with homemade lubes and find that softer seems to be better for preventing leading while improving accuracy and fouling control when shooting black powder. Lastly, I think it is better for accuracy to have the bullet/case better supported in the chamber even though it is somewhat over sized. Sharps has a black belt in BP shooting and his comments are always spot on. Mike is an expert as well and may comment further.

Thanks, Diz

[mike ford]

Leatherman,
In spite of Diz's gracious comment, I'm not an expert, I just "tell a good story". I have found over the years, that Vic is absolutely correct, "Rifles are strange critters sometimes". A couple things to think about: You will be extremely lucky if both your rifles are chambered for the same version of the cartridge; verify that they are really 47mm versions of the MB case( your description of the problem, leads to a suspicion your cases may be too short for the chamber); some older cartridges were paper patched over both bullet and case neck( Swiss 10.4X38R comes to mind); the .002-.003" rule is not really a "rule", rather, it is a preference that mostly applies to hard bullets and smokeless powder; dead soft undersized bullets often work well with black powder, especially paper patched; black powder demands the use of soft lube without petroleum products( unless my memory fails me again, you already do this); unlike target shooters, old German hunters hardly ever handloaded their own ammo, so wouldn't be concerned with over sizing cases( of course we must be). I don't usually use black powder in my old rifles, so if you do, you will find Vic's and Diz's advice/experiences much better than mine. I suggest you "neck size" a full length MB case(11.15x60R) to 10.5x47R w/o trimming, and fireform in the rifle( do this for each rifle). Inspect the formed case carefully, and see if the rifle wants a longer than 47mm case. Using an oversize lead bullet, as you described, is not likely to hurt your rifles, but only you can decide what gives you the best overall results. Don't be surprised if each rifle wants something different. I hope you can find some helpful tid bit in all my ramblings.
Mike

[Leatherman]

Thanks guys. I got out to the range today with the double rifle 10.5 X 47 and was very pleased with the gun. I had 4 fire formed cases which held 62 grains of ff black Swiss topped with my 250 grain .429" bullet which I shot all four with out swabbing the bore. First two were 2" apart but the next two were 2" outside of that. So I suspected the fouling was the problem. The rest of my loads were cases I formed in a home made die which were slightly undersized and had not been shot yet. These formed case only held 56 grains ff black Swiss. With the 250 grain bullet, no wadding. These shot 1350 fps average, 100 fps slower than the four with 62 grains . I swabbed the bores on each shot and the next 4 shots out of the right barrel grouped 2" and was 1" higher than the left barrel. The left barrel grouped 3 shots touching each other with the fourth 1" out . I think I am capable of better. The barrels are crossing about one inch at the 50 yard point I was shooting at. With double rifles often the right barrel is worn more than the left having been shot more and does not group as well as the left. Shooting was done at 50 yards holding the rifle resting my front hand on a sandbag mimicking off hand shooting. This is pretty good right off the bat as this is a pistol bullet with one large grease groove. I am useing SPG lube. I am getting this rifle ready for competition shooting where we shoot 40 yards at 4" round clangers on African game animals . Everyone has to use black powder. I will probably be the only one shooting a German rifle as the last two events everyone had English double guns. Cali ears were all over the place from .360's to .577's. I was shooting a .500 BPE 3" but after 20 shots I felt like I had a concussion and was dizzy for the next day. I sold that rifle and found this one from one of our GGCA members and restored it to like new condition. This is a very pleasant recoiling cartridge rifle combination and the way it is shooting I think I will be very competitive . The only thing is I will have to swab the bores between shots. Some of the guys shooting the straight case cartridges have developed loads with greased wading and seem to be able to shoot their guns the whole course without much accuracy problems. I will be developing a smokeless load for my 10.5 and 9.5 X 47's rifles as well as there are other double rifle competition shoots I will be attending that have no restrictions on type of powder used . Any one have any smokeless load data on these two calibers to start with? I would like to try 5744 or 4198 powders as I have them already.

[sharps4590]

I don't know about a "black belt" but I have been burning charcoal for over 40 years so hopefully a little something has rubbed off....other than fouling. Diz is always too kind. I can see one of your fouling problems already. Using a .429 revolver bullet designed for smokeless powder. I believe the bullet is simply running out of lube. All good BP bullets have large lube grooves to carry a lot of lube. I don't recall ever seeing a modern revolver bullet so designed. As Diz and Mike mentioned lube can be, no, it is critical. SPG in adequate quantity should suffice nicely. You might negate the effects of a lack of lube by adding a grease cookie if you want to continue to use the .429 bullet. That will decrease the powder charge, consequently the achieved velocity but, should allow you to shoot without swabbing your bore every shot. And, with a double rifle, that also carries the caveat that the load still regulate. If the loads are crossing you are short velocity....maybe. Given the age of the rifle and the likely more wear to the right barrel, as you mentioned, it's possible the disparity lies there. I know you shoot a lot and work with a lot of different rifles but can't remember everything you've done. If you don't have it Grahame Wrights book "Shooting the British Double Rifle" could be a big help. Granted it's about British rifles but ballistics don't care what country the rifle came from.

Your 10.5 load is quite similar to mine. I ended up at I believe 61 or 62 grs. of BP under the aforementioned 270 gr. bullet. It hovers around 2 inches out of my combination gun at 50 yards and my bore is less than pristine. Obviously that is only one barrel.

I understand what you're saying about the 500 BPE. I have a Reilly so chambered and with full house BP loads there's no doubt you let off something of significance. That's all due to the 120-135 gr. BP charge. I can't imagine a long string in a match with that rifle so loaded. On the other hand my NFB loads are a pussycat in that rifle.

Oh, no sir, I don't have any smokeless loads for the 10.5 cartridge. No doubt one could be worked up with the powders you mention or others that are suitable.

[Diz]

Leatherman,

My own experiences with double rifles and Cape guns is that they react more to bullet weight than velocity when trying to get them to shoot properly. That statement is for guns where there was more than one bullet weight available.

I tried to find some accurate data for both cartridges regarding bullet weights of the original cartridges and found a rather large variation. The 10.5x47R is listed in COTW as 260 to 293 grains and this leads me to think that your 250 grain bullet is just too light if it is crossing. All I could find for the 9.5 ranged from 175 grains to 210 grains and perhaps someone has better information about original loads than I do.

You could boost velocity by going to FFFg powder and likely would be able to add a grease cookie as Sharps suggested but I am not sure you would get what you are looking for. I might suggest going a good bit heavier and see if they start to shoot apart then cut either velocity and/or bullet weight a little at a time to bring them in. I could be way off regarding your rifles but this has been my experience. Mike and Sharps are far too modest for the experience they have.

Thanks, Diz

[mike ford]

Leatherman,
While admitting my limited double rifle experience has been limited to smokeless powder( it's pitiful to be "po"), I offer the following as sort of an amalgamation of Did and Vic's advice. Your rifles ( the 10.5s, at least) seem to be in the "class" of the 44-60 Win, 44-60Sharps or the very similar 44-60 Peabody with consideration for smaller bullet diameter in your rifle. In keeping with Diz's advice concerning bullet weight and Vic's concerning grease grooves; I suggest you might find benefit with either Lyman# 439186 387 gr or RCBS# 43-385 385 gr bullets, sized to what ever diameter the rifle demands. While these bullets might be a little heavy for your use, shortened versions would adjust the weight, but admittedly would cost you some lube capacity. It is pretty easy to shorten a mold, but instead you might be better off obtaining a quantity of the bullets shorten them to various weights ( size after shortening, to iron out damages), then use the one that works best as guide to have a custom mold made, with due consideration to deepening grease grooves to make up for sizing to smaller diameter. For 4198 or 5744 loads, I think somewhere around 25gr of 4198 or 28 gr of 5744 would be a starting point to adjust up or down. Keep in mind none of the rest of us have any knowledge of your rifle, so you are responsible to set safe limits.
Mike

[Diz]

Leatherman,

I forgot to ask earlier but do you know the twist rates in the barrels? We may be able to put a better spin on things with that info.

Thanks, Diz

[CoyoteJoe]

The famous P.O. Ackley many years ago demonstrated with magnum rifles and jacketed bullets that oversize bullets were no problem so long as they fit the chamber throat. Using a .277" bore he chambered it for his own wildcat "270 Magnum" and ran pressure tests with 150 grain bullets. He then opened the chamber neck and throat to accept 150 grain 7mm bullets and fired the same load with the same pressure. He then progressively rechambered to .30 caliber, 8mm and finally .35 caliber firing all 150 grain bullets with the same powder charge down the same .277" bore with essentially the same chamber pressures recorded.

[Diz]

Ackley also reported that during some tests he fired a 150 grain 8mm bullet in a modified 30-06 chamber which produced a pressure of only 40,700 psi compared to a standard 150 grain 30-06 at 57,300 psi. My guess as to why, is that the 8mm bullet is shorter than the 30 caliber of the same weight giving more freebore and reducing pressure at the critical instant while increasing velocity before the bullet had to swage down. This is pure speculation on my part because so many things stack up when discussing pressures in guns. Also while reporting on this he never mentions accuracy which is essential to the usefulness of a firearm. I am sure Ackley learned a lot from his experiments but he also blew up a huge number of guns doing it. I am no sage but my humble advice is to err on the side of safety.

Thanks, Diz

[mike ford]

Diz,
The 8mm would have also used some of the pressure fireforming to the longer chamber. I agree about erring on the side of safety, and I also have had signs that greatly oversize bullets may give poor accuracy.
Mike

[Diz]

Mike,

When Ackley ran these trials he actually went through the trouble of re-cutting just the neck area of the chamber so the necked up 30-06 would fit properly. No other changes were made that I can recall. It's been a very long time since I read his book so don't hold me to this but I believe he went all the way up to a .35" bullet of the same weight as the 06. I have a lot of respect for him as he tested every theory and didn't accept hearsay on anything. Some of his results were very surprising.

Thanks, Diz

[mike ford]

Diz,
Yes, and even though this forum is for German guns, his testing of Japanese type 38 rifles showed really amazing strength.
Mike

[Diz]

Mike,

I would never have guessed that Arisaka could take what it did. Amazing is the right word.

Thanks, Diz