Newby needs help big time

[fenris]

Have problem
I have loaded some 45/70 with a 500 grain bullet with 50 gr. of pyrodex RS and they key hole with every shot. When I use 60 gr. Of RS the recoil is like a da## mule and the breach jumps open on my 45/70 trapdoor made by H&R 22inch barrel. Not to mention the fact the 60 gr. will back out the primers. The H/R is a Model 1873 45/70 Gov. on the barrel and Little big horn on the breach lock. And can any on tell why the H it shoot about 16 to 18 inches high with the original sights ( a fine blade with small bead on front and tang on rear ). Have a friend that is a semi gun repairman that stated “ They didn’t make this type to shoot only for wall hanging and collecting” I personally do not believe that H&R would make something that was intend only to hang on the wall. Have to say it will shoot a .457 405gr. With 50 gr. Of Pyrodex and hold a group about 1 to 3 in. in Dia. At 50 Yds. Also would anyone by chance know the rate of twist for said rifle.

[Char-Gar]

There could be several causes for the keyholing bullets from improper size to wrong length for the twist of the barrel. I will let somebody else deal with that..

But.... I would not shoot any load in a Trapdoor reproduction that opens up the breech. That is down right creepy. The backed out primers also tells me you probably have a headspace problem.

The H and R were intended to shoot, but it is time for a gunsmith to check the headspace and give the rifle a good going over. I am not a Prodex or black powder shooter, but I would expect you load would not be a overload in a good rifle.

Yes, those carbines have lethal recoil with full snort 500 grain bullets. That is why the Army developed a carbine load using a bullet of 405 grains and a reduced charge of powder. The average Cavalryman could not handle the rifle load in the carbine.

[mooman76]

I don't know about the new ones but the old ones like I got woll keyhole when you don't use soft lead. Like Charger said something id wrong if it is opening up and it needs to be checked out. You can figure out the rate of twist by marking a cleaning rod and puting a tight patch on a cleaning jag and measure how much it turns. Mine shoots high also ( not quite that high)and I was told a lot of old military rifles were designed that way for some reason.

[The Double D]

Battle sights! Thes guns were for shooting man. Aim center of mass and from point blank out to about 200-250 yards or so you would hit the Man. From my old Marine Corps days M-14 battles sight were good to 300 meters.

Backing out primer don't always mean head space. Especially when you have another issue of the block opening.

Also are you weighing charges or loading them with a volumetric powder measure?

If you are weighing the charges of 60 grains of RS on a scale you are in serious over load area for a Trapdoor. (Primers backing out, block popping open, kicking like a mule...)

You should be using a volumetric measure intended for blackpowder.

If this isn't the source of your problems you need to find a Gunsmith who understands Trapdoors, not all do.

Also try black powder it is much less corrosive on you gun than Pyrodex,

[44man]

60 gr's of Pyrocrap only weighs about 39 gr's by weight. I doubt very much he is using 60 gr's by weight because I don't think it would be possible to fit it in the case without massive compression done in stages.
There is something wrong with the gun and it should be repaired. The Pyrocrap pressure is not that high to open a gun. What would happen if it opened early and the case was shot out? :roll:

[georgewxxx]

There's a fix to the H&R problem. Guess it must be a common problem. Go over to Trapdoorcollectors forum and do a search on H&R.

http://www.trapdoorcollector.com/cgi-bin/afrasca/bulletin/config.pl

Several of the poster have had the same thing happen to their rifles. That forum is the definitive trapdoor site on the net....Geo

[Larry Gibson]

Fenris

I've a H&R LBH carbine and an Officer's Model. I've had them for some time. I've also assisted others who've had/have H&R TDs. The twist of the H&R barrels is 1-22" with a groove depth of .458-.459". They are made for shooting not collecting and do quite well with self cast, commercial cast or jacketed bullets. I did not have any luck with Pyrodex in mine and experienced some key holing also. I just moved on to real black powder and duplexed it with 4759. I mostly shoot smokeless powder in mine though. I also experience the BB popping open on both of mine. I went through numerous "fixes" but none held for long as I wanted to shoot service (the M1873 load with 405 gr bullet at 1350 fps) loads in mine. A couple others that popped open were successfully cured with the fix listed over on trapdoorcollector.com so I'd suggest trying that first. I finally replaced both the BBs on my H&Rs with originals. It took a little fitting but was not difficult. That solved all problems and I use both the LBH and OM quite frequently with full service equivelent loads. I can post what I did if you're interested and a few pictures.

Your LBH hits that high because that's what the originals with the barrel mounted sights did. Why H&R set the LBH up like that with the tang site is anyone's guess. I also couldn't figure out why they put a tang sight on the carbine without the standard rear sight and then called it the Little Bighorn" model. Never was such a carbine with such sights at the LBH. Does yours have the OM pistol grip adapter? Mine did but they never put those on carbines either. Anyways I picked up the LBH carbine just to get the grip adapter for my OM. The carbine shot so well I kept it. I've also taken the tang site off and put a M1879 Type III rear site on it. I also replaced the front sight with a Lyman globe with blade. I took a little off the top of the blade and the carbine hits 3" high at 100 yards (100 yard rear sight setting) with the 45-55 load. If your loads are hiting 18" high at 100 yards then you need a new front sight (recomend a post) that is .142" higher than the one on your LBH now.

My favorite plinking load for my H&R TDs is a Rapine 460250 which casts out at .461 and weighs 275 gr lubed with Javelina over 8 gr of Bullseye. These run 1050 fps and are very accurate. My wife took over the LBH carbine and shoots these loads all day long. I cast them with two double cavity moulds at a time so I cast quite a few pretty quick. I load them on a Dillon 550B. My OM is probably my most shot rifle as it always accompanies to the range and else where to be used for fun shooting. I also never pass up a "deal" on commercial cast 45-70 bullets up through 425 gr as these always shoot quite well in the H&Rs.

Any other questions just ask, the H&R TDs are fun rifles and well worth the trouble to set them right.

Larry Gibson

[Kraschenbirn]

+1 on Larry's comments. I've got a the plain-jane H&R Trapdoor Carbine and have, also, replaced the factory rear sight with a refurbished original and correct height front blade. I shoot an as-cast (.459 dia.) plain-based 405 gr RN over 55gr of Goex FFG which duplicates the old military load and prints about 4" high at 100 yds, using the base sight setting. The piece is truly fun to shoot and quite accurate.

Bill

[fenris]

Thanks all for all the Inof. yes the loads of pyrodex are volume using a (CVA powder measure AC1410 10 gr. increments ) not by weight. I cast my own bullets from wheel weights as they are nothing added. Will try some of the items for mentioned.
Mr. Gibson I as well retired from the U.S. Army as my wife says cut that man and he will bleed green. My weapon was a Springfield 03 06 with Scope. Enjoy your retirement you have earned it. I plan on using the rifle for deer hunting this year here in North central Ky.
Like I said the 457/405s do real well with 50 gr. of pyro and can handle the recoil with no problem. Don't figure a need a soft bullet to flatten out when I am already punching a hole the size of a soda can in the game. The BB doesn't jump open until I try 60 with a 500. Have to also say that I seat the bullet out until it touches the lands and groves. think that could be adding to the problem in any way. Also thinking about trying a powder called pioneer what is your thoughts anyone used this stuff. Thanks again all if anyone wishes to send an email fenris@mail2artist.com

[mooman76]

Fenris

I picked up an original Trapdoor a couple years ago and had the same problem as you. I followed someones advice and used soft lead and it cured the problem. It doesn't have to be dead soft but more like 1/20 or 1/30 mix. These guns were designed to use soft lead and I am sure you will find it works allot better. What your bullet is doing is when you increase pressure, it is jumping the lands. The soft lead will form to the barrel and follow the lands better.I also tried the Pioneer powder. It worked ok but I was not specifically impressed either. I guess I would just concider it an ok powder.