doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 450 3 1/4 BPE bullet diameter

Hello all. New guy here needs help. I just bought my first double rifle and I want to duplicate, as closely as possible, the cartridge it was meant to use.
Left barrel is inscribed:"450 3 1/4" Solid Taper Case"
Right barrel has: "120 Gr. C & H no.6 Powder 270 Gr. Papered Express Bullet"

I'm trying to find an original 270 grain PP cartridge, or two, to dismantle so I can find out what the actual diameter of the bullet is and to see the wad arrangement. The only ones I've found so far are in a bunch of 20 for $20 apiece. I don't mind paying 20 or 30 bucks apiece but I don't need twenty of them. I'm still looking but in the meantime, does anybody know what the actual diameter of an original 270 gr PP bullet is for the 450 3 1/4 BPE cartridge?

Any info is very much appreciated.
Thanks.
Hank

The diameter should be a .458 like most others are. BUT you should have a soft lead slug driven thru each pipe to make sure of the diameter.
You don't need the old collectors ammo for this.

Thanks for that Mike. I've never used PP bullets so I've been reading up on it; The Paper Jacket by Mathews and I've read all I can find on the forums. It seems like PP bullets are made less than bore by .002 to .006 thou and then patched to a couple thousandths over bore. At least that's what I get from my reading.
My bore is .450" at the breech end and .444"+/- at the muzzle. The groove is somewhere beyond .470". Can't slug the that much diameter.
That's why I'm curious what the originals are.

Does this one have an odd number of grooves as many have? If so you're probably measuring it wrong.
Bump the slug up in diameter so it fills the groove. Simply tap the slug with a hammer so it swells up to what you need. I'd be very surprised if it's really .470.
I'll send a PM.

Do you plan to load with black powder or nitro-for-black? This will make a big difference as to how you construct your loads, with specific wadding needed in each type of load. I am not experienced in loading black powder, but I know that Paul Matthews has a lot of information about what wads and grease cookies to use.

I believe your bullet diameter should be set in relation to the bore diameter just ahead of the chambers. I would go for a bullet that is bore diameter, so .450" from what you said. You then will try various types and thicknesses of paper for your patch, beginning with lighter papers and working to heavier papers until you get a good seal and see no evidence of gas blow-by when examining your patch fragments.

Another sign of gas blow-by will be some leading in the barrels. Once you get a good seal you will experience no more leading. It's not really difficult.

Several years ago I wrote and self-published a little article that many have found useful:

http://rbsiii.com/PaperPatchedBullets/index.html

Maybe it will be helpful to you.

Good luck!
Curl

A groove diameter of .470 in 450, is not that unheard of. 577-450s often have larger diameter grooves than expected. An odd number of grooves is hard to measure, but they normally measure smaller than actual(not larger), unless a special mic or "V" block is used.A paper patched bullet is normally bore sized(or smaller) and patched up from there.A soft lead bullet, as stated above)should "bump up" if black powder is used. If smokeless is used, it won't likely bump up and a groove diameter( or .002-.003"larger)"naked", lubricated would be used.With BP, non petroleum based lube must be used.Even naked bullets in factory BP ammo, usually has undersized bullets( expected to bump up. 43 Spanish ammo bullet is .433, while my groove dia is .439"),but the rifle will tell you what it wants.
Mike

Hi CptCurl. Thanks for the reply. I've read your article a couple times at least in the last few weeks. Very helpful and fun to read. And,I especially liked the paper patch manufacturing part. My wife's got the same cutter so I'm good to go.
I'm sticking to 1 1/2 Swiss and the recipe on the barrel. I've got some different papers to try. Just waiting for the swage die to show up. This one is .448".
The twist is 1 in 36 so I'll make the bullets 270 gr. like the barrel says.
Hi and thanks DerAmi. I patched a couple of .451" minie balls and 120 grs Swiss and they shot three inches apart at 40 yrds. off hand so who knows. I'll see what it really does when I get the swage die. Patches fell off at the muzzle and no leading. Beeswax/balistol cookie between two .060"veggy wads. I'm going to switch to thinner wads I think.
I've already ordered the die at .448" so for now that's it, but I'm going to get some original cartridges and see what the diameter was they used.

I use the smokeless for black load in my 450, which is 48 gr 4198

Hank,
Generally, if the barrels "shoot apart",the load needs a little more velocity(more powder or lighter bullet), but if they "cross" it needs less.It's important to know which bullet made which hole, and you may have to shoot each barrel at a different target to do it(you should shoot the second barrel as quickly as you can get back on target).The powder shown on the gun(Curtis & Harvey #6)is considered a more powerful powder than is avaliable now, so you wont't likely wind up using the same load.This doesn't mean the rifle is out of regulation.
Mike

Yup, I remember reading that. My .448" swaging die is on the way so I'll make up some 270 gr, PP bullets and I'll shoot from a standing rest and see what happens.
When I first got the gun a month ago I loaded two cartridges with 300 gr, .458", grease groove bullets. One wad between powder and bullet and crimped. I needed 126 grains of Swiss to make it to the base of the bullet. Now, I have to confess that one cartridge I loaded with 1 1/2 Swiss and the other with 3F Swiss. This was before I found and read some original instructions for loading an A Henry 450 BPE 3 1/4 that said DO NOT USE THE FINE POWDER. Oh well. At 20 yards the bullets almost touched but again it was off hand so who knows. I do know the 3F kicked more. The lands got leaded towards the muzzle end. Nothing in the grooves.
I'll patch some 270s and see what depth I can seat them and still keep them from working out of the case from recoil. I love this.....