Fireforming a 30BR

As far as fireforming to expand the necks from 6mm to 30 has anyone done it with 1.510 chamber length? If so did you just trim the 6br brass to 1.500 before firing? Do you turn it first or afterwards?

Have been thinking about getting a used barrel to have chambered with my reamer put on a old remington action just for fireforming. What powder are you using for fireforming?
 
1.500 is good as the grow in length when forming without a bullet. I personally use a heavy dose of Bullseye with a wax or clay dab to seal it.
 
My purpose for fire forming first is to have a straighter neck. I don't care for expanding first on either caliber. I expand after the first fire forming and it doesn't work your necks as much.
This is my experience, your's may vary.
 
alinwa said:
HOleee Krapp......somebody else said it. OUT LOUD! ThanxAl al
Click to expand...

Yeah...people get way too hung up on "...minimal this and minimal that...." for every dimension.

While there certainly are areas that need this control, the case @ .200 ahead of the extractor groove and the body/shoulder junction aren't areas that you want to have too snug-ish relative to the chamber dimensions. Like a high maintenance female, there's nothing to gain and only trouble when it acts up. ;)

Even a little bit of bulge at the back end doesn't bother me, if everything else is good. It's all about the sizing. Connect the dots to the high maintenance female reference...;)

Wrestlin' with the bolt and upsetting the gun in the bags while your condition is just hanging there and begging for a couple more to get sent down range is when the light bulb usually goes on.

Like 'The Dude' says in the video link below....just my opinion. Good shootin'. :) -Al

https://youtu.be/pWdd6_ZxX8c
 
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Fire forming 30 BR

I know this topic is old . I fireform my 30 BR directly from 6 BR brass in a stainless 12ga x 30 BR insert I got a machinist to make me. 10 grains of Unique, small pistol primer, COW and top it with cast bullet lube. Then, inside neck ream it so outside neck reamer pilot fits inside and outside neck trim to .010". Much more concentric than using the expanding dies. Works for me.
 
danyboy said:
I know this topic is old . I fireform my 30 BR directly from 6 BR brass in a stainless 12ga x 30 BR insert I got a machinist to make me. 10 grains of Unique, small pistol primer, COW and top it with cast bullet lube. Then, inside neck ream it so outside neck reamer pilot fits inside and outside neck trim to .010". Much more concentric than using the expanding dies. Works for me.
Click to expand...

WOW that's a great idea ;)

I'ma make some up with screw-in endcaps where I can change the size of the exit hole to change the pressure curve.
 
danyboy said:
Don't quite follow you. Why change the pressure if end result works fine ?
Click to expand...

I FF cases from 220R/BR- sized to 50BMG through many caliber changes......I won't use COW. In fact I don't like to use anything like putty, wax, clay etc..... I use only powder and a tiny wad of tissue.

Some, like 30BR or even good 6PPC require more backpressure than this system allows for so I've been using bullets....... I _think_ I can effect this via gas escape hole changes.
 
ues a sub caliber bbl with a no throat reamer, then use a sub caliber throater....
22, 20 17 cal bbls for gas control
there you go
 
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