Issue with 300 WSM brass in a Tikka T3 light.

thepolinator

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Hello All,
I am attempting to reload .300 WSM. I have been reloading other calibres for about 6 months now and I have not run into this problem before. Essentially, my rounds are very difficult to chamber. I checked the overall case length and cartridge length, they were at or below SAMI spec on all of the rounds I tried. I was able to determine that the overall length of the cartridge was considerably longer than the actual chamber length of my rifle (Tikka T3 light), despite the cartridges being within the SAMI recommendations. I had to back the overall length back to 2.70 inches to make the cartridge fit; however, that did not fix the overall issue.

It appears that the cartridges are binding right at the neck when being chambered. I am using RCBS dies and have attempted both full length and neck only sizing of the brass, both of which has the same result. At this point I am beginning to think that my problem is that my chamber is too tight to accommodate standard SAMI sized brass. Have any of you ran into this problem before? Any ideas what the cause may be? If it is an overly tight chamber, are there sizing dies available that size to the minimum SAMI specs instead of the standard/ maximum size?
Thanks in advance for your help.
 
My friend ( I don't reload for any WSM calibers) says that he has a "Hell of a time" re-sizing the brass compared to his other calibers (.308/30-06/.243 etc) maybe it is just harder to move that brass back to original specs. Is it nickel plated to boot??
 
I had a similar issued resizing one of my short mag (can't remember if it was my 7mm SAUM or my .300 WSM)? Anyway, the issue is that the short brass are pretty stiff. Even when I was setting my die with a slight cam over on the shell holder, when I was trying to full length resize, even at the full stroke of the press, I could still see light between the shell holder and the die. The shoulder was not getting bumped back enough for easy chambering. I had to set the press with a harder cam over to get the brass to be fully resize. May or may not be your issue.
 
If the stubby cases are stiff, you may also get more spring back than normal. Try FL sizing and holding the ram at the top of the stroke for a few seconds before lowering it. Might make a difference, might not.
 
I have had a number of Win brand 270 and 300 WSM cases that were loaded to very high pressure from the factory. Even after FL sizing (yes the dies were set so the press would toggle over centre) The brass was very tight and hard to chamber in any rifle I attempted to chamber them in. I have not had the same problem with Rem cases in the SAUMs or the WSMs or Fed cases in the WSMs. Later Win ammo seems to be loaded to slightly less pressure and the cases re-size normally.
 
I had the exact same problem in the exact same rifle using the same dies. I had to bump the shoulder back a little more and have had no issues since. FL size every time and I haven't had an issue for about 5 years, make sure you cam over on the press and that should work.
 
I have had a number of Win brand 270 and 300 WSM cases that were loaded to very high pressure from the factory. Even after FL sizing (yes the dies were set so the press would toggle over centre) The brass was very tight and hard to chamber in any rifle I attempted to chamber them in. I have not had the same problem with Rem cases in the SAUMs or the WSMs or Fed cases in the WSMs. Later Win ammo seems to be loaded to slightly less pressure and the cases re-size normally.
I wouldn't say the pressure of the previous load has as much to do with what you encountered as the hardness of the brass.
Winchester WSM brass is known for being overly hard to start with, often splitting necks on the first factory firing (an issue caused by hard brass, not high pressure). I would attribute this to causing your problem far more than high pressure.

As with many sizing problems, try annealing the brass. It makes the brass more malleable, easier to form, and more inclined to hold it's shape after sizing. It solves 90% of issues with sizing.

High pressure loads do appear to harden the brass but you usually need dangerously high pressures to do this. I'm talking 70-80k psi or higher.
 
I have found, with both the 270 and 300 WSM cases, that the shoulders were not being sized properly to allow proper chambering. With the 270 WSM I eventually had to remove 0.008" from the shell holder to allow the case to go far enough into the die so that they would chamber in my BLR. The combination of a very small chamber in the typical BLR and the need to set the shoulder back to SAMMI minimum specs was a challenge to trouble shoot initially.

Shortly after I shortened the shell holder I found an article in a shooting magazine wherein the author made the same discovery as I and, to correct the situation, had shortened his die. I preferred to experiment with a $7 shell holder rather than an expensive die, with the same results.

The first thing I would try in your case is to make sure the press has no play (especially if it is a turret press) and make sure the ram is camming over quite substantially. It wouldn't hurt to cam over twice as well. Then, as I do with all the WSMs now, I chamber the first few empty resized brass in a batch, in whichever rifle it is intended for, and make sure they will fit.

Let us know the outcome.
 
Steep shouldered, straight sided cases have been the darling of wildcatters for years, but ever notice that the factories avoided them like the plague? After the .284 Win it took a lot of time before anyone jumped back on that horse. More standard tapered cases are easy to form and thus resize, and the factories aren't overly concerned with case life. They are concerned with handling rifles with feeding problems though. The WSMs can be touchy to size, theres a fine line between not touching the shoulder and slamming right into it.Or moving it or crumpling it. Add some press flex and it gets worse. I've got a couple WSMs currently and find the use of the Redding competition shell holders helpful. With those you can set your die to cam over hard and still play with shoulder bump at the same time. Good little cartridges with their little quirks.
 
I adjusted the cam to the maximum possible setting and found that it made a difference. The cartridges still bind a little bit; however, the action closes much easier now.
Thanks for all the advice.
 
You might also be having a problem if you seating die is set so deep as to start to crimp. Those shoulder will flee out very easily. Try running the sized brass through you rifle.If the problem exists with sized brass you have to move the shoulder back. If it is only loaded ammo you should be backing off the seating die or trimming the brass shorter

Neilm
 
I experienced the same problems with my .300 WSM. Previously it had never been necessary with any other calibre to cam over. With the WSM it is imperative to use maximum cam over. Annealing also helps.

Jim
 
The infamous "shoulder bulge" is what your encountering.
Short fat and squat with a jaunty shoulder is the culprit.
Take a few thou off the shell holder and all will be solved.

Been there done that.
 
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