Pressures?

[RG300WSM]

I'm setting up my 300 WSM again and am having pressure issues at low charges. I have been FLS and bumping back my shoulders .002. Trying to work up a load but I'm getting the ejector mark and a hard bolt lift at only 2 grains above minimum load in the berger book with h4350 and h4831SC. I decided to set up my FLS die like the book says to and not worry about the .002 so now its sizing my brass back to factory specs which I know will probably end up ruining my brass quicker.....

I had this same issue with my 7mm when I set it up. Started working loads with new brass. Found one up at the high end of the book loads that didn't show any pressure or hard bolt lift. Resized my brass bumping my shoulder back .002 then went out and shot and blew the primers right out of the case ha.

Just curious if anyone else has had this issue before and what did you decide to do?

The gun I'm setting the load up for is a 300 WSM built off a Remington 700 action with a 22" proof barrel using berger 210 gr vld hunting bullets.
New Norma brass headspace length is 1.733
After the shot headspace is 1.741
Have been resizing to 1.739
Seating my bullets .010 off the lands.

H4831sc start load is 57.5 gr and max is 64.0 gr. Im getting pressure signs at 59.5.

 

[PddPdd]

Hodgden's reloading website doesn't include a load for a 210 grain bullet and 4831SC but does for H4831, which should be similar, with a starting load of 58.3 and max of 66.3 compressed.

In my experience it's difficult to use a bullet over 200 grains and have enough room for the powder in the 300 WSM but that may vary with the brand of brass you are using.

You might try a search on 300 WSM and Berger bullets.

I have loaded lighter bullets for that caliber with 4831SC.

Specifically to your pressure issue, I find new brass will take higher charges due to the pressure being absorbed to some degree by the deformation of new brass to the chamber dimensions. After first firing I had to reduce charges to avoid over pressure.

Hope this helps

 

[RG300WSM]

So I'm shooting the stuff I sized back to factory specs and just shot 60.5 gr of h4831sc with no pressure issues. It sucks because it's only 25 degrees here so it's hard to know what it'll do at 80 degrees but I have the loads sitting on the defrost heater in my truck until I'm ready to shoot them to try and get the casing hot. But so far it looks like sizing them back to factory is helping with the pressure. It does show the sc in the berger book for 210's but I've never used it in the past. I've always shot h4350 in it which is what I'll try next. I want to get a good group with 4831 and 4350 then decide between the 2 on what to use

 

[PddPdd]

Do you know what kind of velocities you're seeing? How is accuracy?

 

[RG300WSM]

Do you know what kind of velocities you're seeing? How is accuracy?

Not sure on velocity yet but I have a couple groups around the .5 moa with the 4831 so far. The velocity is hard with this rifle where the barrel is so short. Its not real exciting when I chrono it haha.

I think another thing is the brass is pretty much at the end of its life it looks like haha. I've reloaded this stuff 5 or 6 times. Starting to get a few with the shiney line at the head. So im guessing thats probably giving me some false pressure too.

 

[PddPdd]

Agree, that case isn't going to last much longer. I recommend reducing your loads when fireforming new brass to maximize brass life. Maybe even lighter grain weight, cheaper bullets if you have them.

.5 MOA is good. What range?

 

[Rich Coyle]

I had a 7Mag like that. I settled on a load firing a starting load that averaged 3,284 with a 140 grain Barnes.,

 

[Seabeeken]

How is the H4350 doing?
I'd toss that case in the scrap bucket before it separates

 

[RG300WSM]

Agree, that case isn't going to last much longer. I recommend reducing your loads when fireforming new brass to maximize brass life. Maybe even lighter grain weight, cheaper bullets if you have them.

.5 MOA is good. What range?

Right now I'm just shooting 100 yard groups

 

[RG300WSM]

How is the H4350 doing?
I'd toss that case in the scrap bucket before it separates

Just started shooting the 4350 in it. 4350 was what I was shooting in it before I had it re done. Yep all the shiny lines are getting scrapped and what doesn't have a shiney line in this batch will go in a drawer for in case of emergency brass haha.

 

[PddPdd]

I would test out some varying seating depths at 100 yards with the powder of choice. Then re-verify that I have the OCW followed by checking my accuracy at the range I plan to hunt/target shoot at, weather permitting.

 

[Koda_]

Just curious if anyone else has had this issue before and what did you decide to do?

had the same issue with low charges/velocity but getting high pressure. Took me a while to figure out but found I had a really bad carbon ring in the chamber. The rifle is 20is years old so no surprise. Im getting it rebarreled.

 

[Seabeeken]

^^^^^^^^^^^
This

 

[RG300WSM]

had the same issue with low charges/velocity but getting high pressure. Took me a while to figure out but found I had a really bad carbon ring in the chamber. The rifle is 20is years old so no surprise. Im getting it rebarreled.

Dang! This one is brand new it's had 50 shots through it now so that knocks me out of that one.