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jason brown

i thought id share something iv been looking into.

first im not an expert by any means, and figures quoted are just my experience, with my rifle. they may be very dangerous in your rifle. do your own measuring for your rifle.

so i brought this up a while ago but i cant find the thread. it was about case length and to be exact case neck length. i was wondering if there was anyone measuring there "true" case neck length for "there" rifle.
im not sure if there is a lot of benefit or if it was even worth the effort. but i figured more case neck length might mean being able to seat a bit further out if seating for contricity. and the obvious less case trimming.

well it turned out it wasn't a hard or expensive exercise. but as far as worth while well that's up to the reader.
i got these plugs from sinclairs when ordering a few things.
there called "Sinclair chamber length space gauges"

you basicly trim a case back real short, put the plug in and close the bolt on the now modified case which comes out maximum length.

my results were...
over all length was 2.5475 inches which is for my 7mm magnum
the standard book trim length is 2.5 inches.
they recommend that if you do leave your case length to grow, to set the over all length .024 less than the actual over all length of your chamber.
(the reason being explosive if you don't, as far as i understand)
so that leaves me with 2.5230 i can stretch it out to.
.023 inches over the book trim to length.

as a novice i always used to trim to about 2.4990 to make sure im under the trim length. its good to know i can let the cases grow some what or that i have a bigger margin than i thought. so far i havnt let the cases grow there sitting right on 2.5 but i plan to.

so yeah, that's my novice experience with chamber length gauges.