Sizing Question??

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Sizing Question??

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11 January 2009, 04:26

HEAD0001

Sizing Question??

I just purchased an Encore barrel in 45-70 chambering. I am currently having a gunsmith do a little custom work to the barrel. I am having him do a MB, and install a Skinner rear ladder sight. I asked him to do a casting . The casting measured .4575 at the breach, and .4582 at the muzzle. I normally cast a Lyman 405 grain bullet for my 45-70's.

I have a Lyman sizer. Normally I size my 45-70 bullets to .458. What size do you guys think would be best for the barrel measurements I listed above?? Thanks, Tom.

11 January 2009, 07:05

vip

I'd probably try the .458" first and see how they work. IF accuracy is poor than I'd go to .459" Paul..

11 January 2009, 09:47

swheeler

quote:
Originally posted by HEAD0001:
I just purchased an Encore barrel in 45-70 chambering. I am currently having a gunsmith do a little custom work to the barrel. I am having him do a MB, and install a Skinner rear ladder sight. I asked him to do a casting . The casting measured .4575 at the breach, and .4582 at the muzzle. I normally cast a Lyman 405 grain bullet for my 45-70's.

I have a Lyman sizer. Normally I size my 45-70 bullets to .458. What size do you guys think would be best for the barrel measurements I listed above?? Thanks, Tom.

Looks like they chambered the wrong end of that blank, slightly choked at the muzzle would be better.

11 January 2009, 12:28

303Guy

Two questions;
How reliable were those measurements?
Is the bore evenly tapered or is the muzzle 'flaired'?

One wonders whether profiling of the barrel resulted in stress release which allowed the barrel to expand.

12 January 2009, 01:38

HEAD0001

Measurement was done by a professional with Cerosafe(not me). Taper-I do not know that. That would be hard to find out with a casting(or impossible??). Tom.

20 January 2009, 19:48

bfrshooter

If the measurements are right, that barrel will never shoot good, it is backwards. Sort of like shooting a revolver with smaller throats then the barrel.
Next, I do NOT trust Cerro-Safe measurements. Slugging is the best way. Upsetting slugs in the bore is even better.
It doesn't matter what size boolit you use in a backwards barrel. It will be too small at the muzzle.

20 January 2009, 20:50

starmetal

Too bad you had your gunsmith modify the barrel. You may have talked to TC about the bore dimensions and seen if they would make things right...new barrel.

You can lap the breech end of the barrel. Firelapping is one way. Usually in firelapping the breech end, ends up being larger because the lapping compound gets used up in that area first before reaching the muzzle.

22 January 2009, 16:43

Not to start a debate or hijack the topic, but this kind of thing is why I stopped buying any barrels from TC and only get my barrels from custom smiths.

If anyone has the time, check out the bore dimensions of TC's 44 and 357 caliber barrels.

23 January 2009, 10:15

Singleshotlover

well if it was me I would hand him back the rifle and ask them to get another one and repeat the test. Most shooters like the taper concept. Unfortunately your taper is bigger at the muzzle than at the breech. Should be the other way round. I'd size to .459 as I like my bullets at least .002 over groove diameter. Frank

23 January 2009, 10:26

303Guy

quote:
You can lap the breech end of the barrel. Firelapping is one way. Usually in firelapping the breech end, ends up being larger because the lapping compound gets used up in that area first before reaching the muzzle.

I was wondering about that!

23 January 2009, 10:57

HEAD0001

I mentioned lapping to the gunsmith. He said that might work. But then he said that the overall difference is 7 ten thousanths. And then he said that I should first shoot the barrel, before doing anything else. So I ordered a .459 sizer die today. I should be getting the barrel pretty soon, and I am going to shoot it first.

I wonder if you can get fire lapping bullets for a 45-70?? Tom.

23 January 2009, 16:28

LBT has firelapping compound that you can use with cast bullets.

If the bore is in good shape, it should not take more than 20-30 rounds to get it polished.

23 January 2009, 18:06

Concho42

In another post of mine I had a very bad experience with TC junk barrels .50 Will never buy another !

26 January 2009, 19:11

bfrshooter

I owned several TC's over the years, sold them and never went back.
If you want a .45-70 handgun that will clang steel to 500 meters and shoot under 1/2" at 50 yd's, get a BFR revolver with a 10" barrel. No MB needed. Pleasant as heck to shoot.

30 January 2009, 05:48

HEAD0001

I spoke to the fellow at LBT. He said his lapping kit would even out the diameter inside the barrel. So I guess I will give it a try. He did say I may have to go to a .460 bullet. Tom.