Turning down OD of bull barrel to suit bushing.

Hello to you all

I have a small Hercus lathe at home and need to turn down the OD of a really good comp bull barrel to standard barrel bushing size for a Briley spherical barrel bushing.

I am building a 6" PPC gun in 38 Super on an STI "Perfect 10" 2011 foundation.

I have a 4 jaw and the lathe is in good condition.

My background is in engine machining and whilst I have done work on firearms before with good results, I wanted to run this one by some experienced minds.

What are your thoughts on setting up the job?
It's a $500 Ray Pulver barrel that I waited 6 months for (In Australia wait times for this stuff tend to be long) so I really don't want to go about the job in the wrong way.

Should I just pay a smith? Seems like such a simple job but I have never done one before.

Thanks in advance.

About all I can help with is, I have talked to Krieger about having one of my barrels re-contoured. They would only go down two sizes. From what I gathered, the concern was inducing stress and changing the internal deminsions.

Also, somebody posted a video on YouTube (its also in the bulletin on accurate shooter.com) showing the bore of a few barrel muzzles changing after turning and threading the muzzle for a 5/8-24 thread. Hope this helps.

Set it up in the 4-jaw and take light cuts. This is a pistol barrel and we cut them all the time to fit. We usally cut the area between the chamber and bushing a couple of thou smaller too give bushing clearance and reduce wear.

How does the lock or valving work to trigger the pressure ?
Ie how do you get a measured amount of air, only, per shot.

Any data, links, plans much appreciated.

lukefenech said:

I am building a 6" PPC gun in 38 Super on an STI "Perfect 10" 2011 foundation.

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MilGunsmith said:

Set it up in the 4-jaw and take light cuts. This is a pistol barrel and we cut them all the time to fit. We usally cut the area between the chamber and bushing a couple of thou smaller too give bushing clearance and reduce wear.

Click to expand...

Thank you Milgunsmith.

If it were mine, I would chuck up a piece of steel in the headstock chuck and turn a snug fitting stub arbor for the chamber end. The muzzle would run against a live center in the tailstock. That way the finished OD would be dead nuts concentric with the bore.

BTW Briley's spherical bushings are the only way to go for my money.

RWO

Could you ream/hone the barrel bushing to match the barrel? Always less stressful to modify the cheaper part.

RWO said:

If it were mine, I would chuck up a piece of steel in the headstock chuck and turn a snug fitting stub arbor for the chamber end. The muzzle would run against a live center in the tailstock. That way the finished OD would be dead nuts concentric with the bore.

BTW Briley's spherical bushings are the only way to go for my money.

RWO

Click to expand...

Yeah a good idea RWO. Thanks

Scottl said:

Could you ream/hone the barrel bushing to match the barrel? Always less stressful to modify the cheaper part.

Click to expand...

I hear what you are saying there Scottl but the barrel is so fat it needs to be machined either way. No avoiding it. Getting hold of the correct size Briley spherical barrel bushing in Australia is turning out to be an interesting task... I want a spare spherical ring as well and the big parts supplier in the US I usually use no longer lists spare rings. I emailed them and the parent company to try and source the parts I need last night..See how I go. Parts would be so much less stressful if I lived in the U.S.