Soft alloys for undersized bullets.

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Singleshot S.A.
PostsCOLON 81
JoinedCOLON Sun Aug 30, 2015 6:19 pm
LocationCOLON Adelaide. Sth Oz.

Soft alloys for undersized bullets.

Post by Singleshot S.A. » Mon Mar 20, 2017 4:26 am

Hi all,

I have been shooting a slightly undersized bullet, (.409) in my 40/65 which measures .410 groove diameter with some reasonable success. The bullet would not work at 25/1 and I was ready to get rid of it until I realised that my Muzzle loader mix is much softer than this so I tried a softer mix which started at 50/1. It halved the group size immediately. Another bonus, at .409, it breach seats easily with the softer mix.
I shot at a different Club than normal last Saturday, one which has some very good BP shooters, and the guy directly alongside me told me (after discussing the .409) he shoots a PB bullet 4 thou under size in his M/L. I watched him load it ( it nearly fell down the barrel) and it shot one large hole in the bull at 100.

So........ who else shoots undersized bullets. ?

I understand that the bullet will upset (expand under pressure) and that obviously helps, so why do most casters and mold makers recommend 1 or 2 thou over size. Or is this mainly for the harder alloys. ??

Is there a different requirement between muzzle loading and seating the bullet in a case. Or breach seating. ??

Just wonderin. Because as I see it, if the bullet is say 2 thou over size, and then it has to swage itself into the bore, where does the extra alloy go ? Does it leave a nasty tail on the base..............

Brent
PostsCOLON 1587
JoinedCOLON Sun Nov 20, 2005 9:12 pm
LocationCOLON the most boring real estate west of Illinois

Re: Soft alloys for undersized bullets.

Post by Brent » Mon Mar 20, 2017 5:56 am

I shoot bore-diameter (land diameter) bullets in all of my cartridge rifles. I use the same bullets in my muzzleloaders as well. But they are not soft. They are almost always 16:1. The bullets start out at .443 or .444" and then are patched to .450-.451" and finally bump up on ignition to .458. They are the most accurate bullets I've ever shot and they work out to 1000 yds.

I'll be bringing a bunch of them to Adelaide this October to shoot them in my muzzleloader at the International matches.
I'm not from here, I just live here.

Singleshot S.A.
PostsCOLON 81
JoinedCOLON Sun Aug 30, 2015 6:19 pm
LocationCOLON Adelaide. Sth Oz.

Re: Soft alloys for undersized bullets.

Post by Singleshot S.A. » Thu Mar 23, 2017 3:39 am

Great Stuff Brent,

Bring everything you've got, I'll take it. lol.

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