Reloading for break actions?

[scythefwd]

I have read, specifically on bellmtcs.com, that you need to set the shoulder back about .001" when using the TC line of break actions, both the encore and the contender.

Why would that be? If the round sits against the frame and is seated in the chamber on the shoulder, why would you want to have the setback? I don't get why you wouldn't just neck size the brass and trim to length like you would on a bolt action.

This comes up right now with me because I am about to start reloading, and I have a break action rifle. It is a CVA though, so there might be a reasoning behind the setback on T/C's that I don't get. I have less than .04mm gap between the frame and the barrel when closed. Factory Winchester rounds sit about .02mm below the end of the barrel, but Federals and some hand-me-down reloads are flush with the end of the barrel. The case of the round doesn't contact the frame till it is full closed and locked, so I don't see any problems with getting pushed too hard into the lands of the rifling here. The extractor lowers the round into the chamber as it closes and makes all contact with the breech face (what do you call that part of the frame???) instead of the case.

Thanks for any input.

 

[243winxb]

With any break open, the locking lug must be fully engaged. A t/c might not fire if not fully locked. Other break opens like a Savage 24v O/U can pop the action open all by itself on firing a round, a weak spring can be a problem here. There is no camming action on break opens like a bold action has, so you must have the correct cartridge headspacing to chamber a round. The .001" is a tiny amount, will not hurt brass at all. Basic rule, if you have to use extra force to close the action with a round loaded, compared to an empty chamber, you need to FLRS more, pushing the shoulder back.

 

[Scrapperz]

Giving yourself that .001" play in head space ensures easy loading on break actions. It's not a problem for the case.

 

[R.W.Dale]

Not only does it ensure proper ignition and ease of operation but it's critical to uniform latch engagement which can cause vertical stringing like you wouldn't believe. As will brass sized too much. IMO this is why rimmed or belted rounds work best for this action. With rearward headspace control you can bump the shoulder back like any other rifle and have the rim-belt control headspace in a nice consistent manner.

Break action rifles are an entirely different kettle of fish in terms of brass prep that must be played by their own rules. The good thing is your bbl (with the extractor pulled aside) makes a great case gauge

 

[scythefwd]

Thanks for the info. So I am seeing it correctly, but the .001 (which is about .02mm, or half the thickness of my smallest gauge) is a safety measure. I plan on using my chamber to setup the dies, and once set leave it. I only own 1 firearm in this caliber, so it isn't that big of a deal in this case.

Looks like I need some FL sizing dies.. good to know before I bought.

Krochus and 243 - didn't think about the locking lug and the force it can apply.

243 - I figured that if I needed any extra force to chamber the round and close the chamber, something had gone wrong. That is something I look for in my bolt actions too.

Thanks again all, I get it now... and anything that keeps a reloader from unsafe consequences (opening while firing) is a good thing.