enlarged case head

[Red Dawg]

Having a bit of a problem with the case head on my 270 wsm. I know they are historically known for very high pressure but just wondering if anyone has any ideas as to what could be going on. I shoot a model 700 cdl stainless fluted.

[Huntbear]

Can you post a pic?    Is the bolt lift sticky after firing?  Primers backing out?  Splitting case necks?  Are these reloads or factory ammo?  A lot of things may be causing it.

[Red Dawg]

primers are not backing out at all. They are flattening a bit. No split necks just a slight bulge near the head of the case. Seamed a little bit hard to lift the bolt. I was using 58.5gn of imr 4350 but I backed it off to 54.5 and it seemed to help although it is not perfect. It did shoot better groups though and seemed to function a little bit better. I also trimmed my brass from 2.1 to 2.095 and shortened my coal a bit from 2.65 to 2.58.

[Red Dawg]

the only other thing that I can think of is that the brass is molded a bit to small. Seems a bit smaller than what the nosler and hornady book call for.

[Jamieb]

Without knowing your load(bullet,powder,primer) I dont know if the load is hot.
If theres no other sighs of pressure then it sound like you might have a batch of brass that soft.
The best load I found for my 270wsm is 130gr tsx's over 69gr. of H-4831 with a CCI-250 for 3250fps.

[Red Dawg]

the thing that is pissing me off is that the rifle showed these signs with remy factory ammo and also with my hand loads which I used winchester brass. Maybe I need to try another brand of brass since all of my brass measured under the saami specs for diameter of the case head area, nosler does not make 270 wsm, any ideas as to another brand that I could try out.

[Jamieb]

I just measured some fired/unresized 270 wsm brass, fired in a Tikka T-3 lite. According to the case drawing in the noselr book my cases are expanded more then they should be in the case head area. I've been getting 6 reloads out of Win. brass with no failures so who cares about the head expansion. I'm FL sizeing so alls good. One note about this 270wsm. I cant partialy full length resize. I have to full length resize in order for the brass to chamber. This is the only rifle I have that I dont PFL size for. I could probably get more reloads out of my brass but I'm not going to push it WSM brass is cheap and I'm way to lazy to anneal necks.

[257 Wby Mag]

My old ruger 6mm does this too. Full length size em and rock on.

[Huntbear]

If factory ammo is doing that too, I would take the gun to a gunsmith and have a chamber cast made, and the measurements taken off the casting.  If it is out of spec, then it is your chamber, not the brass.  You have to remember, they chamber as many barrels as possible before changing reamers at the factory.  If you get one chambered towards the end of the reamers life, there could be issues.  Just a thought.

[Red Dawg]

The thing huntbear is that the brass comes in under spec. I dont know why, but like Jaime said once I full length size the brass it is good to go. Although I have made up my mind that I need to find a gunsmith that will do just that, because it will bother me until that end of time until i get it perfect. Any ideas for a good gunsmith that could do this work for me. I dont know of any.

[Huntbear]

Chamber casting is an easy job for any gunsmith.  I am not from your area, so know of no one to help you out.  Check older posts about guys needing gunsmiths, there have been several posted.

After thinking about this some, it may just be what it is, and as long as FL sizing works, great.   You just may not get as many loadings out of your brass.  I would stay away from max or near max loads though, just for safety concerns.

[Jamieb]

Red Dawg PM sent.

[Red Dawg]

thanks jaime for helping me sort out my problem.

[Jamieb]

Nice chatting with you. One of my hunting partners called today asking for help finding him a deer rifle for his daughter, I loaned him my 270wsm for the season. Hopefuly she'll fall in love with it and they'll buy it from me, then I'll put the money twards a 7mm wsm.

[Red Dawg]

the funny thing is I was doing some research about the 7mm wsm last night myself. Looks like a great round not sure why it never really took of. I was just thinking having someone build me one out of my 270 wsm. But I also want an alakan ti. Well see what happens next year.