300 WSM reloading and chambering problems

[itchytriggerfinger]

how did you establish you were 30 thou off the lands and was the ammo all from the same lot number

The lot numbers on the inside bottom of the boxes, I measured the Federal Ammo with a comparator and measured a pulled bullet CBTO with the Stony Point gauge. The factory Ammo seemed to vary as much as 7 thousandths but it was between 30-37

 

[Hunterjones]

.007 thousandths variation isn't atrocious for run of the mill factory Ammo. That is around twice the size of a human hair.....

 

[Rick Richard]

Rick,
I don't have any H4350, I have a bunch of IMR 4350, one or two lbs H1000

That will work, but a slight difference in burn rate than "H".

 

[Rick Richard]

After 10 rds? I cannot see any ring or carbon buildup with the bore scope.

Doubt very very seriously a carbon ring will form after 10 rounds.

 

[itchytriggerfinger]

Do you mind posting a pic of your throat area? A couple from the neck area forward could help. Did I miss what you were cleaning with (bronze brush, just patches, etc)?

I'll try to get some pictures tomorrow, I clean with bronze brush for the majority of the cleaning, transition to nylon in the end so I not chasing copper introduced by the brush.

 

[JAYgs8163]

Is it possible the chamber is so short or tight that the neck of the brass is being contacted more than it should be when chambered? Then acting is if your brass is too long and pinching the neck? My questions are to help me learn also as I'm getting ready to build a 300WSM.

 

[wbm]

Been there done that with the 300WSM. Had the same problem with two custom barrels...discovered that the problem was that the headspace on both was set too tight and my dies were not short base so they could not adjust down that much. Solution? I reset the headspace for a bit more "slop". Problem solved!

 

[RuninL8]

So, I have recently seen an increase in very tight chambers, you need to check your headspace first and foremost. Now, you can do this yourself by renting a go-gauge and learn something or send it back to the builder. If the headspace checks, you need to measure your brass and make sure you are bumping the shoulder at least .002 back. Something is wrong if you are getting hard lift and brass is flowing in primer pocket. Message me if you want futher info, on checking headspace I can walk you through it.

 

[tokatee]

To the OP. I have had the same experiance with my custom, the 300 wsm. is my favorite cartridge, I have five different rifles in it. My first is a BLR. Browning, the next is a 700 sps.,then come a Mossberg 4x4, after that come my custom 700, 22" heavy fluted Krieger 9 1/2 twist,bedded Bell Carlson, have shot under 1/4" but still working with it, my last is a Savage ultra light, absolutely love it! To the problem you are having, I thought I could use so my brass in all my rifles, no way, the sps.and the Browning will, the Mossberg and Savage I have to run the brass through a small base then I'm ok and they shoot under 3/4" as does the sps. Now getting to the custom it will not use brass from any others with out problems, and the Smith told me a precision chamber will need it's own brass and I use the small base die with it.
Now we have had problems with Federal brass being way soft but you should be able to reload the Myfactory brass that was shot only in that rifle though you will probably have loose primer pockets. Start with a lighter load and see what happens.

 

[nksmfamjp]

make sure you are bumping the shoulder at least .002 back.

To me, this is the key. With a good FL Die, good lube and a rigid press, you need to be able to size your cases until you can just close the bolt -0.002". If you can do that, you should be good. If not, I would send ammo, fired brass and rifle back to the gunsmith to better understand chamber issue.

 

[slikmrc]

Has your gunsmith seen the pictures of your fired brass? The staining on the primers doesn't look good, looks like your close to blowing primers. I've seen and heard of a number of factory loads showing pressure the last few months. I don't know if it is the rifles or ammo but it seems to be an issue as of late. You could put a piece of scotch tape on the head of a new case and see if it chambers. It should chamber, and would let you know you have at least .002 head space. If it does chamber I would suspect a neck/throat issue and send it back to the gunsmith.

 

[jdyoung]

Rsnell : The Ammo was Federal power shock 180 gr soft pt. I have not shot reloads. I cannot chamber sized brass that has not been fired in this chamber. I did pull a bullet and weighed the powder charge at 69.0 grains but not have identified the powder.

Rick: spoke to the builder, he did not seemed concerned, he did indicate that it is a short throat and it was like a " race car". He did offer to rethroat it but said I would sacrifice accuracy. He basically said I should be working up a load starting with virgin brass. Which is exactly what I would do IF I COULD FIND ANY...lol
I thought the next best thing was to break it in using commercial Ammo and then reloading it.

Casual: I cleaned the chamber with alcohol after every cleaning so I am sure that residual solvent or oil is not an issue.

As far as seating depth, I am at least 35 thousand off the lands.

What really has me twisted is why, of the same lot of ammo and almost identical conditions were the first ten shots fine and the next 20 were not? What could have changed? I mean, I realize it is a very gradual process but as the round count increases, the throat erodes slightly and that should alleviate pressure somewhat. Which makes me think, it should have been the other way around, showing pressure signs with the first shots and lessening with the subsequent shots. Or am I missing something? Below are pics of the first ten cases fired.

Make sure you clean the throat !!!!!!!! And if it was me, I would have the smith look at it, not over the phone stuff. Then if you think it is feasible, have him add a couple thousands to the throat.

 

[muledeer01]

I would send any unused ammo back yo federal along with a few fired cases, let them look them over. I sent .300wsm back to federal and they agreed they were over pressure and refunded my money.

 

[LoneTraveler]

You are in a not wanted situation right now. Caught between the Rifle Builder and Federal.
I would call Federal and discuss the ammo with them.
I would contact him and make arrangements to return the rifle.
I would not fire any more loads in the rifle until someone gets the problem resolved.
Every shell fired through is putting stress on the parts and could cause damage.
Be Safe and Good Luck in finding the problem and getting it resolved .