Home Forums Hunting & Shooting Ask The Gunwriters Tight chamber?

I recently acquired a 338-06 and started working on running some Nosler 30-06 brass through my Lee 338-06 sizing die. I adjusted the die down until it made contact with the shell holder and ran a piece of brass through. Loaded the empty brass into the chamber, and the bolt had to be forced closed. Hmm, need more shoulder setback. I ended up adjusting the die down until it cammed over pretty hard. Sized the same piece of brass and tried chambering again. Better, but I can still feel a bit of resistance when I close the bolt. Tried switching from my RCBS shell holder to the Lee. Same thing. Is there any reason not to shoot as it is? I am sure it won't stick in the chamber so hard I can't open the bolt, nowhere near that tight.

Will I run into pressure quicker if I shoot as sized now? Or would you just shoot it as is? I wonder if the chamber was cut on the tight side, and if so, makes me curious to whether it was on purpose. It is a BRNO Mauser with an aftermarket barrel, my gunsmith said if he had to guess he would guess a Douglas barrel.

My understanding is I could solve the problem by getting a machinist to grind .008-.010 off the surface of my shell holder, and I am not opposed to going that route. There is a good machinist just down the road from my place, I am sure he would do it for me.

What does the neck O.D. measure with a bullet seated? If you're sure the tightness isn't from inadequate neck clearance, you could fire a couple.

If you haven't necked the brass to .338, the tightness could also be from the .30 cal neck being forced into the .338 rifling.

That fired brass could then be used to properly set your die up.

Good shooting.' -Al

I will need to measure the O.D. once I get home this evening. The brass was already necked up to 338

I had the same issue once with one of my 7mags.I was using RCBS dies.I bought another set of RCBS dies,set them up the same and the brass chambered without any problems.Now as for the Nosler brass,I bought some 30-06 brass once.I could not chamber the brass in my 30-06 without resizing it first.Once I ran it through my dies,it was fine.I use Lee dies for my 338-06 too.When I make my brass for my 338-06,I use once-fired 30-06 brass,usually Winchester brass.I've never had an issue with my brass.You might be getting some spring back on your Nosler brass.If you can get some once-fired 30-06 brass of a different brand,try making some 338-06 brass and see if your still having the same issue.

I have some Hornady and Rem brass as well, I will try them to see if there is a difference.

Also, make sure the case neck isn't bottoming out at the end of the chamber neck.

Just a few things to check before firing a few on an unknown chamber..... -Al

Not sure I understand how to check this? I do know after necking up my brass the length was shorter than the "trim to" length in the manuals.

Also, the fact that the fit was "less tight" as I screwed the sizing die in farther...does that not mean it is a tight headspace issue?

You might want to start using virgin brass, I had the same thing happen with new barrel from McGowan, it would not chamber pre fired brass from another rifle had to start using virgin brass.

This happens with my custom 8" twist 270 WSM. The smith used a really "minimum" reamer for it and though headspace is fine, my RCBS dies don't size the base of cases I fired in the original factory (win M70) 270 WSM barrel quite enough for resistance-free cambering. Said brass also gives a false "stiff bolt lift", which would feel like an overpressure load if you hadn't felt it on closing.
I use virgin Hornady brass and it works great for LOTS of reloadings. Very impressed with that brass. Wish I could find another couple boxes of them. On the wait list at a bunch of vendors.

Good luck with your 338-06. Great chambering.
Rex

Does the Nosler '06 brass (you don't mention whether it's new or 1x) chamber before you mangle it in the Lee die?

No it does not

And it is fired brass

Try some new brass.

Dies just like chambers have a spec. You have a min spec chamber and a max spec die. Had the same problem. Try different set of die’s. Hasbeen

I've used the Redding Competition Shellholder Set #1 (308 Winchester, 30-06 Springfield, 45 ACP) when I want to control sized case headspace to solve an issue the OP is having.

This is after I've confirmed that the case neck mouth is not impinging on the chamber case neck shoulder.

For what it's worth I bump shoulder to allow 0.002" headspace.

Do you have a 45ACP sizing die? If you do try running your rifle cases through it after taking the decapping pin out etc. The head/web expansion of the case may be the problem.

Brownell’s chamber length gauges

Some 45acp dies aren't deep enough to allow 30-06 family cases all the way in. I have a 45acp die I had the top bored through and works great for squeezing case bases.

From .17 to .338, I use 'em all the time....there's a lathe made .375 in there, too. There's also additional ones for tight neck chambers. -Al