Any one tried the 300gr SMK in a 338win? I've been trying to find some load and performance data on this but I've not found much other than some guy claiming 2500fps in an unspecified rifle. I'm interested in trying it out for some longrange target shooting 1000m+ range. Failing this the 250gr SMK bullets work well and I've got a load for them.
300gr SMK in a 338win?
- Thread starter HeadDamage
- Start date
- Location
- Somewhere on the Hudson Bay Coast
Sierra does not recommend a fast twist in their data for the 300 gr MK, so I doubt if you will experience stability problems with it. I also doubt that you will achieve 2500 fps with this bullet from in a .338 Winchester, even if you have a long barrel. If you are able to achieve that velocity, chances are it will not be the most accurate load you could choose, and in long range shooting, accuracy trumps velocity. You should be able to hit 2400, and with the high BC of that bullet it will be a good choice as a long range bullet. If this isn't enough I suppose you could rechamber to a large capacity, powder eating round like the .338 Lapua, .338/378, .338 Ultra, etc.
According to my ballistic program, the 300 gr MK starting out at 2400 fps at sea level remains super sonic to 1455 yards. Work up a good accurate load, don't worry to much about the muzzle velocity, as long as the numbers are consistent. A couple of weeks ago I surprised myself with a group I shot at a GPS'ed distance of 1038 yards. This was with my .308 shooting a 200 gr MK chronographed slightly below 2400 fps.
According to my ballistic program, the 300 gr MK starting out at 2400 fps at sea level remains super sonic to 1455 yards. Work up a good accurate load, don't worry to much about the muzzle velocity, as long as the numbers are consistent. A couple of weeks ago I surprised myself with a group I shot at a GPS'ed distance of 1038 yards. This was with my .308 shooting a 200 gr MK chronographed slightly below 2400 fps.
Should have looked in my Sierra Manual. It says 2400fps from a 21.5" barrel but the OAL is longer than standard so it will not likey fit the mag but would still be fun to play with. I'll have to pick up a box and give it a spin 
Right now I've been pushing the 250gr SMK out of my 24" Ruger at about 2725fps.
Right now I've been pushing the 250gr SMK out of my 24" Ruger at about 2725fps.
Although I've never shot any 300 grain bullets in my 24" Ruger .338 , with 275 gr. Speers and max load 73.0 gr Imr4831 my readings for a 0.90 inch group at 100 yards were : 2688..2627..2652 ft/sec.
Max load with 73 gr. Reloder 22 1.10 inch/100 yds: 2545..2572..2561 f/s ...one grain over this at 74.0 produced pressure signs with: 2688..2706 two shots only
fired as primers flattening...
2500 f/s with a 300 gr might be safely done with Imr 4831...
hs45/70........your mileage may vary
Max load with 73 gr. Reloder 22 1.10 inch/100 yds: 2545..2572..2561 f/s ...one grain over this at 74.0 produced pressure signs with: 2688..2706 two shots only
fired as primers flattening...
2500 f/s with a 300 gr might be safely done with Imr 4831...
hs45/70........your mileage may vary
