Well this was my first time loading for this bullet and assumed that since it was a magnum I would use large magnum primers! Well after looking in nosler, barnes, and hornady book they use large rifle primers. Is this going to badly effect my loads or my gun? It will be shot out of a 24" Olympic arms ar upper.

Here's what I have
87gr vmax
A4350 powder at 40.3 grains
Fed 215 primers

243 WSSM

Thanks for your help

Pressures and velocity will most likely be a little higher. You are using the hottest primer available. According to the Accurate reloading data you are near the starting load so should not be an issue.

http://www.accuratepowder.com/wp-content/uploads/2011/01/accurate_load_data_3.5.pdf

Ok thank you very much sir.

I shot it twice with no noticeable signs of pressure but it was very dirty. The first round cycled but the second did not. Do I need more fps for it to cycle in an ar?

Just FYI here is a good place to get brass or custom loads cheaper than anywhere ive seen in the 243 WSSM.
www.reedsammo.com Reeds Ammo

I would expect it to cycle better and be a little cleaner burning at higher pressure levels nearing Max loads for it.

Sounds good. I loaded some 62 gr varmint grenades that are suppose to be running 3865fps so hopefully those will do well.

Thanks

If you use a Magnum Primer most manuals who rec. standard primers
tell you to reduce you load by 2 grains. You will get a pressure
spike usually. Most weapons perform well on game at 2500 fps or more muzzle velocity..The old 30-30 was around 2100fps to 2300fps. and it worked well out to 1-200 yds if shot placement was good. Sounds like you are trying to get more than the load
is rated for, if you wish to overload have the weapon throated 5%
and you can overload it slightly which will burn out you throat faster..DD

What powder are you using to get the 243 wssm down to to 2500fps ttrailboss? that is a barrel burning beast of a caliber

Both loads cycled well and shot 1/2 in groups at 100 yards!

Glad to hear it. Sounds like a good load to stick with.

I am have issues with my Dtech 243 WSSM AR-15. I am using nickel plated winchester 95 grn vmax which I think might be the culprit. The rounds don't eject all the way and sometimes cause a double feed or jam when the spent brass goes back into the chamber. When I look at the spent brass it is marred up from the ejector and sometimes the neck is dented or expanded. I think the winchester rounds were made for a bolt action and cant handle the pressure in a 243 wssm ar platform. Has anyone had this issue before?

My Olympic .243 wssm upper has behaved perfectly with H4895 pushing 105 grain speer hot cores. I've had problems with both W780 and RL19. I'm continuing to experiment, so I don't have a definitive answer as to the exact problem yet, but my guess is that near max loads of slow burning powder create an unhappy combination.

Regarding regular vs magnum large rifle primers, the rule of thumb that I've always heard is that loads above 60 grains of powder should use magnum primers. Also, some ball powders are harder to ignite than stick powders, and so are suitable for use with magnum primers. Most quality reloading manuals will indicate when a powder requires magnum primers.

I found a guy in Rosebud, Missouri that is well educated on 243 WSSMs and is loading me up some 105, and 115s to try out. He was very helpful walking me through the ins and outs of 243 WSSMs. $45/box and shipping out within the week. They also do a deal where you can send them your rifle for $250 and they load up custom rounds for it. http://www.coppercreekammo.com/