Home Forums Reloading Big Game Rifles Primers for 300WSM

I may give it a shot when this brass is done. I wish Lapua would make my life easy and just produce 300WSM.

I think im going to start at Hodgdon min and try again. I did manage to get a couple of sub moa 3 shot groups. I honestly think some of the other groups were me more than the loads. I typically have the range to myself but there were about 4 other shooters yesterday. Just didnt feel like I was shooting my best.

Heres a shot of the primers, 2 on the left are my loads, the one on the right is the factory load. A wise man on this site says flattened primers dont mean much as far as pressure is concerned. Outside of that, I didn't see anything else besides velocity that would indicate I was pushing it too hard. I stopped at 64gr(3k fps) Even then I only shot 1 round just to measure speed.

I



d really like to shoot the 62.6 loads again, first group of the day on a new rifle. SD/ES numbers looked alright, fell like it should have shot better. Other than that, nothing really seemed to jump out at me.

I wouldn’t worry so much about the flattened out primers as I’ve seen those with some factory loads, especially Hornady Superformance rounds. If the gun is a bolt gun check the brass for rings down low. Also are there any bolt lift issues? Those would be my main pressure concerns.

I definitely understand about the range. I quit going to public ranges a few years back. Now I pretty much only shoot at my hunting club range which is 300yds. If people are they before I’ll just go back to the camp and try another time.

Yes those are pretty flattened. Are all of those targets with 180 E-tips?? 62.8 looks really good.

I see it’s TTSX’s now. How long is your barrel? You’re getting some really good velocities compared to what the book shows.

Its 25in. Well, the rifle is Blaser R93 so no bolt lift but ive heard you can get the same effect with pressure as far as not being able to cycle the action. I had no issues with that. Mule Deer says flattened primes in of themselves mean nothing. Old wives tale I suppose.

I think I may reshoot a few of those. I just couldn't see to get settled behind the gun but had already made the trip to the range and just really wanted to get some chrono numbers. Our range is private but since its the only one around it has quite a few members. I usually avoid Saturday but it was busy week.

62.8 and 62.3 are on the menu. The first 2 shots velocity wise were close, it was the 3rd shot in both groups that opened them up. Could be me or something not lining up during reloading. My main concern being that these are only .050 off the lands is that I really dont want to seat them any deeper and push the pressure up. Its been my experience with Barnes that they may want to be out as far .90-100. Plan B is to start at the bottom of the book load and see what happens, although Id like to keep the velocity higher. I also have some 180 Nosler AB coming as well as 165 and 175 Barnes, 150 and 165 AB's on the shelf.

I agree with mule deer, I wouldn’t put much weight into the flattened primers.

To me the 62.8 load looks promising both velocity wise and grouping especially if you think you may have not shot your best group.

I’m not extremely familiar with the Hodgdon powders as I usually use IMR’s and reloader. Another option that will be similar to the 4350’s is RL-17. Although I couldn’t duplicate the accuracy of the IMR4350 a lot of people really like it for wsm calibers.

On another note, once you starting trying the AB’s and E-tips take a look at the Nosler book. They have load data on a bunch of different powders.

Ohh and I understand your concerns with wanting to keep the pressure down but I always load mine to the coal either the Barnes or Nosler book shows depending on the bullets I’m loading. I know a lot of people say to load monos close to the landings but actually seating them deeper has given me better accuracy. I have copied a pic of the same powder charge and same coal (Barnes recommended) just using TTSX’s instead of AB’s. Results were almost the same. Who knows maybe I flinched a hair.


https://i.imgur.com/xqxXI6y.jpg

I generally stick with H powders as I have big swings in my hunting temps so I typically stick with temp stable powders. I do have some reloader here though if all else fails.

Not going to try etips, just the AB's. Looking at the nosler book now. I think Barnes says to start .050 off and work further away. I factored my oal based off the readings from the oal tool. Still have a box of ttsx 180s to burn up.

I almost always run the cci 250 in my wsm's. They always seem to work well. Don't be afraid to go down to the 150 ttsx if you want to shoot ttsx's in your wsm. I've shot the 150 diagonally through a moose. Superformance will drive 150s at 3400 from a wsm and that's all the weight you need in a monolithic. The 150s are extremely accurate in my rifle. If you go lead core I like a 180 or even the 200g NAB.

Bb

I plan to have both a 180 and 150 load.....although I do have about 10 boxes of the 165gr TTSX sitting here.

Increasing primer brisance basically always improves temp stability on the low temp side, since the problem is fundamentally getting the powder lit.

Depending on the load lower brisance primer can work fine, but if I have to pick one that's not the direction I'm going to go for a hunting load.

CCI 250's for all .300 loads.

Makes sense

Im a CCI primer fan myself but in the magnum realm, the CCI seem to have the most reported issues and are the least recommended.

I have been using them for 25 years with zero issues. I used to use Winchester back in the day and did have a couple of misfires with those. Switched over to CCI and have had no issues.

Flattened primers do not mean much, but when the primers fall out after four loadings, it does mean the load is too hot for the brass.

I often load one piece of brass multiple times to test for primer pockets becoming loose.

Primer choice? I have never found any thing better than CCI 250s in 30-06 or larger capacity using 4350 or slower powders. I would start with H4831 in your WSM, and perhaps experiment with Accurate Magpro or Ramshot Magnum as they are very dense and you can get high charge weights without compression.

The slowest powders in the IMR Enduron line look promising, but I have no experience with them at this time.

Yep, I'd be looking at the 62.8 gr load and adjusting the oal a bit.... Maybe seat them a hair deeper...

Some really good information here. Thanks to all.

Yes sir, tired some of the more promising loads over again with the 1x fired brass, no flat primers or powder crunching. As I mentioned in an earlier post, the primer pockets were VERY tight on these to begin with. I assume that had to do with the flattening. The 1x fired brass was also easier to seat the primers this time.

I had palnned to try 4831 but due to the initial case capacity on the Norma brass being less than most brass,I wouldn't be able to get enough powder in to get to the velocity I was after without running compressed loads. Im pretty much sold on the Extreme pwders from Hodgdon. Ive had excellent results in all temps with it thus far.