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browning b78 case sizing

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03 April 2023, 20:53
Mike Ray
browning b78 case sizing
I have a browning b78 in 25-06 that I have had a while and never shot it. I have a question on resizing the brass. I realize full length sizing will chamber, but on a bolt action I just size enough for case to chamber with just a little resistance( the way to do it according to Hoyle, and the reloading Gods), so what should I do for this rifle? thanks in advance.


No matter where you go or what you do there you are! Yes tis true and tis pity but pity tis, tis true.
05 April 2023, 14:44
Peter Connan
I see no reason why the process should be any different unless doing that gives you some sort of (unforseen by me) problem?
07 April 2023, 05:30
Mike Ray
well me neither but i've never reloaded for this type action and wondering if there might be other things to consider.


No matter where you go or what you do there you are! Yes tis true and tis pity but pity tis, tis true.
07 April 2023, 06:58
eagle27
A little resistance when closing a bolt action is acceptable as the only parts that are 'strained' for want of a better word, are the bolt lugs and lug abutments in the receiver. This is not so with other types of actions where not only are the lock up surfaces involved with any 'strain' but so are various hinge points, pins and cams found in all other types of action.

Apart from if setting up cartridges to fireform e.g. bullet up against lands etc., it is generally not recommended to have cartridges so sized (or unsized) to put any excess strain on the these other types of actions. Any wear at multiple points will compound.
The Miroku (Japan) manufactured Browning will be made of the very best steel so a little resistance is not likely to affect it.
13 April 2023, 18:28
Upstate Greg
You have mechanical advantage (camming)on a bolt action to chamber neck sized only rounds, not so with any single shot action. It's best to full length size cases. You can just neck size the brass after being fired for the first time in the single shot as the brass will only expand to fit that particular chamber.
17 April 2023, 18:47
Mike Ray
thanks guys for the advice, I was thinking there should be little resistance.


No matter where you go or what you do there you are! Yes tis true and tis pity but pity tis, tis true.
20 April 2023, 11:42
Peter Connan
quote:
Originally posted by Upstate Greg:
You have mechanical advantage (camming)on a bolt action to chamber neck sized only rounds, not so with any single shot action. It's best to full length size cases. You can just neck size the brass after being fired for the first time in the single shot as the brass will only expand to fit that particular chamber.


Not necessarily true.
Falling block actions with the mortice slightly angled (and there are many) can have a huge amount of camming force. Far more than a bolt I action.

As long as the cartridge can be pushed into the chamber far enough that the rising block's front surface can get behind the case (instead of the block "jamming" under the rim), one can normally get the action to close. But good luck getting that cartridge out again!
23 April 2023, 06:54
Craftsman
quote:
As long as the cartridge can be pushed into the chamber far enough that the rising block's front surface can get behind the case (instead of the block "jamming" under the rim), one can normally get the action to close. But good luck getting that cartridge out again!


True.

Also when I partial size my B78 in 6MM Rem I can not adjust the sear to minimum engagement. If I do the sear will disconnect. You can have shallow engagement if you full length size.


Craftsman