I have 2 Ruger 264 Win Mags that are stainless Ruger model 77s.They are throated for factory ammo which will not let you use almost any other bulley.I found a throat reamer in 264 by clymer that my gunsmith can use.I am getting 3/8" groups with 155 gr Lapula bullets at 200 yards with H-870 powder.They are seated about 1/2" short to be able to chamber in this rifle.I do not want to loose my accuracy but I would like to full seat these bullets.I think I can get 4 or 5 more grs of powder in the case and at least 150-200 fps.I am afraid that if I ever have to shoot anything with all four rounds that the recoil will drive the bullets into the case and make them loose.It did this with the 160 gr hornady when I tried deep seating them.I am asking should I have the rifles throated for the 155 gr lapula or even deeper for the hornadys so I can use any bullet made.I dont want to loose my accuracy.

I wouldn't worry about throating.....If your bullets are being driven into the case, sounds like your magazine isn't long enough, either.....As far as having to shoot four shots at something,(game?), the Lapuas probably aren't game bullets anyway.....Gaining maybe .250 inch seating depth won't get you anywhere near "4 to 5" more grains powder capacity... And if you're using H-870, your probably running a well compressed load now........
Finally, if you are getting .375 inch groups at two hundred yards with your Rugers, you best have them insured for much money, and locked up in a safe place!! For you have the two finest .264 Magnum rifles ever crafted by the hands of man!!! My two pre-64 Model 70s, cal. .264 Win. Mag. will only shoot into about 2 1/2 inches at 200 yds, on their, (and my) best days.....Grant.
Oh! Older Winchester factory ammo, used to be loaded with a two diameter bullet.....This was to keep too much of the long .264 bullets from protruding into the available powder space.......The front part of the bullets were a smaller diameter than the rear driving portion....At one time, Hornady made a two diameter bullet for the .264 Mag. But I e-mailed them, inquiring as to the availability of these bullets, and they never answered my query......

I suppose we should figure a way to shoot 155 gr target bullets at game from a SAMMI chambered 264 WM. On the other hand I will take the easy way out and suggest 140 gr hunting bullets.

My old M70 shoots pretty well now at 200 yds but never that well. When it shoots worse than well I don't know who to blame

These Lapula bullets are awesomew on game the mega tip.I am glag I bought two of the Ruger stainless.I have almost a half inch left in my mag when I load these bullets as the throat is now.I use up to 69 grains of H-870 now with a longer throat I think I could use up to 75 grains with the 155 gr.My rifle would not shoot groups under 1.25 with the remington 140 gr bullets.I was very suprised with these Lapula bullets.I might try their 140 gr bullets also.I just wanted to seat the bullets all the way out to magazine length which is a half inch longer than now.The 140 gr remington corelocks are alright but I love these lapula bullets.

I am going to try to throat one rifle and see if it works out.I hope so any way.It sucks not being able to use any bullet except the remington 140 gr for reloading.