Reloading 300 WSM

EE_Reloader

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Michigan
Hello All,
I am loading for a Tikka T3 chambered in 300 WSM. I am using AGD brass and I have bumped the brass 5 thousandths using a sinclair 35 degree bump gauge insert. This will be the 3rd or 4th firing on this brass. The issue that I'm running into is difficulty closing the bolt. I suspect the base of the brass is not being sized enough. Has anyone else run into this when loading for their 300 WSM rifles. Any input or help would be appreciated. Thanks.
 
I just had a similar issue with clickers. Bought an Eric Cortina FL sizing die and it fixed the problem. It sizes the brass smaller down by the .200 line. Also, Micron Precision makes one that does the same thing. Both are expensive so Newmexkid's suggestion of Redding body die might work and save some money
 
Hello All,
I am loading for a Tikka T3 chambered in 300 WSM. I am using AGD brass and I have bumped the brass 5 thousandths using a sinclair 35 degree bump gauge insert. This will be the 3rd or 4th firing on this brass. The issue that I'm running into is difficulty closing the bolt. I suspect the base of the brass is not being sized enough. Has anyone else run into this when loading for their 300 WSM rifles. Any input or help would be appreciated. Thanks.
Could you be running into bulging at the cartridge belt, have you measured your brass diameter at this end?

Issue appeared for me also when firing cases numerous times and condition is belted-case-bulge.

There is a "belted magnum case die" that will resize your case at the bottom by Larry Willis (larrywillis.com / Innovative technologies) and if you do buy one, be sure to use lots of case lube. The son took the business over and makes these in lots and I think you are lucky as he might have just done a production run. If not in stock, you might have a few months of a wait.

Plenty of youtube video's on the topic, just use this for your search term: 'videos of larry willis case die 300 win mag'. You can also look up 'belted case bulge' to see some exaples.
 

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yes I had this exact issue with Norma brass (Tikka, as well). The body mentioned by newmexkid solved the problem.

If you want to provide it to yourself, color a piece of brass with black sharpie (like layout paint) and cycle it a few times. The wear will show you where it is tight.
 
Have you trimmed the brass yet? You may be running into the end of the chamber with the case mouth.

Also if you are not annealing you may have to set your sizing dies down a couple thou to keep your shoulder bump the same as it was with new brass.
+1 on what Longbomber says ……
Check overall length on your fired cases that are giving hard bolt close. Compare to virgin brass (air your reamer specs if you have it). I run my 300WSM on a heavy competition schedule (read lots of rounds). I re-confirm case length on an entire set of brass before reloading … will normally need to be trimming perhaps a 25%-33% of my cases each time. Verify length also with an unloaded and un primed case that does not give you hard bolt close …. You will likely see it is a few thou shorter. Ultimately decide on a (Max) trim length you want to you comfortably for your brass/chamber combo .. then periodically check (and trim/chamfer) as needed.

Drop me a line if needed … I can likely tell you suggestions on lengths to try as a starting point….. always best to know your chamber details as starting point.
 
I use ADG brass for mine, most of which are virgin cases at this point. But when I was using federal and Norma cases I would get a stiff bolt closing. Make absolutely sure the cases are within spec length wise and use a body die! I've notice with this cartridge and a 270 WSM that both chambers are tighter than my standard cartridge chambers to begin with. After talking to several local GS I think it's partly just nature of the beast with these short magnums in a sense. My virgin ADG brass chambers like a dream compared to the other once fired cases that I've loaded.
 
Hello All,
I am loading for a Tikka T3 chambered in 300 WSM. I am using AGD brass and I have bumped the brass 5 thousandths using a sinclair 35 degree bump gauge insert. This will be the 3rd or 4th firing on this brass. The issue that I'm running into is difficulty closing the bolt. I suspect the base of the brass is not being sized enough. Has anyone else run into this when loading for their 300 WSM rifles. Any input or help would be appreciated. Thanks.
Jeff did an excellent job in this video, which might help resolve your issue, be a good practice, or add to your growing knowledge base. Take your time and enjoy the learning process.
 
Hello All,
I am loading for a Tikka T3 chambered in 300 WSM. I am using AGD brass and I have bumped the brass 5 thousandths using a sinclair 35 degree bump gauge insert. This will be the 3rd or 4th firing on this brass. The issue that I'm running into is difficulty closing the bolt. I suspect the base of the brass is not being sized enough. Has anyone else run into this when loading for their 300 WSM rifles. Any input or help would be appreciated. Thanks.
Before you spend $$ on a new body die run your die down in the press 1/16 of a turn size a piece of brass and see if it chambers. Keep turning down die until brass chambers easy. I usually have a gun smith chuck my die in his lathe and take .010-015 off of die so I don't cam over my press. Also Redding make a set of shell holders that are .002 differs heights
 
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