Swapping BBF receivers, should one worry about headspace?
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- Gun Barrel Ecologist
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Swapping BBF receivers, should one worry about headspace?
Here's a curly question for the boffins:-
If one has two BBFs with interchangeable barrel sets, after developing a safe but optimum load with the barrel set attached to one receiver, should they be worried enough about subtle dimensional differences in relation to the breechface of the other receiver to commit to repeating the load development process?
Of course some would suggest that with a BBF the rounds should be kept at a low pressure and such miniscule variation wont have an influence, however I have an old 7x57R barrel set that refuses to group low pressure loads
If one has two BBFs with interchangeable barrel sets, after developing a safe but optimum load with the barrel set attached to one receiver, should they be worried enough about subtle dimensional differences in relation to the breechface of the other receiver to commit to repeating the load development process?
Of course some would suggest that with a BBF the rounds should be kept at a low pressure and such miniscule variation wont have an influence, however I have an old 7x57R barrel set that refuses to group low pressure loads
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Re: Swapping BBF receivers, should one worry about headspace
I think you will be OK. When they fit a set of barrels, they hone on the lock up lug on the barrel. As long as it locks up tight, you should be all right.
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Re: Swapping BBF receivers, should one worry about headspace
Unless the 2nd set of barrels had been gauged and fitted to the recover then I wouldn't recommend doing it.
Think of it like swapping the bolt from a 243win with a bolt from a 308win from the same model of rifle, it might be fine, but then they only need to be out by a bit.
Think of it like swapping the bolt from a 243win with a bolt from a 308win from the same model of rifle, it might be fine, but then they only need to be out by a bit.
I'm soft and I don't care.
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Re: Swapping BBF receivers, should one worry about headspace
I have seen one fit, no gages where used, they just honed it until it closed tight.
- Gun Barrel Ecologist
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Re: Swapping BBF receivers, should one worry about headspace
So other than adjusting the FLS die to the new chamber length (?) what over precautions would you see as necessary?SPEEDY wrote:Unless the 2nd set of barrels had been gauged and fitted to the recover then I wouldn't recommend doing it.
Think of it like swapping the bolt from a 243win with a bolt from a 308win from the same model of rifle, it might be fine, but then they only need to be out by a bit.
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Re: Swapping BBF receivers, should one worry about headspace
Gun Barrel Ecologist wrote:So other than adjusting the FLS die to the new chamber length (?) what over precautions would you see as necessary?SPEEDY wrote:Unless the 2nd set of barrels had been gauged and fitted to the recover then I wouldn't recommend doing it.
Think of it like swapping the bolt from a 243win with a bolt from a 308win from the same model of rifle, it might be fine, but then they only need to be out by a bit.
I would at least want it checked with a set of go-no-go gauges.
I'm soft and I don't care.
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- Meister der jagd
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Re: Swapping BBF receivers, should one worry about headspace
This is what several Blaser people have told me over the years, some were USA people, 2 were from Germany;
If the new barrel fit on to the reciever and the gun closes and locks you are good to go.
Sometimes the new barrel will need to be fitted in the hinge area, and sometimes in the locking hood area, sometimes both.
I bought a second set of barrels for my D99, from a buddy. We just tried them on my reciever and the fit was perfect.
I have shot them a bunch and no problems.
However this set of new barrels will not fit my other D99 reciever...
If the new barrel fit on to the reciever and the gun closes and locks you are good to go.
Sometimes the new barrel will need to be fitted in the hinge area, and sometimes in the locking hood area, sometimes both.
I bought a second set of barrels for my D99, from a buddy. We just tried them on my reciever and the fit was perfect.
I have shot them a bunch and no problems.
However this set of new barrels will not fit my other D99 reciever...
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- Meister der jagd
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Re: Swapping BBF receivers, should one worry about headspace?
I wouldn't worry about it. Tolerances are so close on new Blasers as to be a non-issue. The headspace will be fine.