Thread: Brass tight in chamber

I am probably making a rookie mistake so hopefully someone here can help me out?

Am loading for a 7saum, using Norma necked down 300saum brass.
Redding full body die.
Am not as disciplined as I should be with my brass, however has been fired approx 6 times?
Currently have some pieces that will chamber fine and others that are exceptionally tight in chamber.

Have compared all dimensions of the brass as best I can, can not identify any significant difference between those that will chamber and those that are tight?

Tried winding down die to bump shoulder back more but no joy.
Thought the neck may be getting a bit thick from repeated firings but on comparison it's hard to see any major difference?

OAL: 2.025
Neck width: .320
Base width: .550
Shoulder width .535
Average neck wall thickness?: .019

Any insight greatly appreciated

Tight on body?
is the brass tight to chamber or just to rotate bolt down?
vivid mark a tight case right down one side and chamber a few times, it should show you where it is tight.

Cheers a VC. There appears to be contact approx 5mm above the rim. Pretty sure this brass is nearing its end as there is a fain't ring present at this point in all brass which I assume is an early sign of case separation? Just assumed that resizing woul return brass to chamber specs so confused as to why the tight fit?

Just tried to upload photo to "my album" to demonstrate. Right hand case tight fit, left hand fine.

What is the rifle? I had a rifle rechambered and found that the sizing die wasn't sizing the base as the chamber dimensions were less than the die.

It's a Tikka T3 Bremic. Do you know if there is an easy way to test this theory apart from gunsmith? Cheers

So are you trying them as unloaded brass first so
Just chambering on empty case?

Sure am Camo. Have fired a few of the last batch which were getting tight, still shot fine but not to keen on doing too much more before sorting it. Have measured every aspect I can think of using calipers and can find no real difference between tight brass and stuff that's fine? My brass discipline is shit so no doubt the tight one would have had a few more firings... Maybe just time for a fresh batch and a more organised approach?

Have you measured from the base to the shoulder?
Got any that are chambering sweet to compare too?

Yup have compared the two using calipers and can't find any difference? All brass was resized at the same time using same dies so it's got me stumped

Checked from base to neck/shoulder junction
On case that chambers and one that doesn't?

trim length might be worth checking even if its not

base to shoulder headspace datum check with case that feeds nice

case diameter at the widest point just in front of the rim

get new brass or maybe try a small base sizer

Originally Posted by Link

Cheers a VC. There appears to be contact approx 5mm above the rim. Pretty sure this brass is nearing its end as there is a fain't ring present at this point in all brass which I assume is an early sign of case separation? Just assumed that resizing woul return brass to chamber specs so confused as to why the tight fit?

Originally Posted by Link

Just tried to upload photo to "my album" to demonstrate. Right hand case tight fit, left hand fine.

I cant see the photos anywhere? click the little picture of a tree next to the picture of film in the reply box.

It sounds like the body above the web needs resising and your die is not doing it enough for your chamber.

The marking could just be from die and chamber touching up the brass but not the base, best bet is section one and have a look if worried about imminent case head separation, any noticeable thinning at the web/body junction you may as well bin the brass IMHO.
otherwise a body die of smaller base dimensions may get you a few more firings.

Scoped and Cam yea guys have tried those measurements as best I can with my kit an no noticeable difference, have a feeling my methods and gear may not be quite precise enough. Cheers VC whacked that picture up and I hear ya reference the case head separation. Have heard about dies not quite sizing the base, sounded weird as I assumed it is a universal chamber dimension but seems highly probable? Cheers guys for all the info will just look at getting some new brass as this lot has had a fair hammering over load development etc...