Mk248 mod 1 reloads
- Thread starter Jgrovem110
- Start date
Here you go. Pretty much Everything you ever wanted to know about the Mk248 Mod 1....
http://www.snipershide.com/shooting/threads/mk248-mod-1-ammo.93043/
One thing to think about: the military doesn't have to worry about reloading the brass, so the H1000 load in that cartridge is hot to the point where the brass may not be reloadable.
http://www.snipershide.com/shooting/threads/mk248-mod-1-ammo.93043/
One thing to think about: the military doesn't have to worry about reloading the brass, so the H1000 load in that cartridge is hot to the point where the brass may not be reloadable.
Ok thanks I’ll check that out for sure , yeah read that I might mellow out the load slightly to avoid that issue
You might want to consider a bullet with a better BC. The Sierra 240 is an improvement, Bergers et al even more. Better BC means less drag, less velocity loss so less drop, and shorter flight time so the wind affects it less. It seems improbable that you will find 248 laying around anywhere.
Separate issue: if you can find government once-fired that is WW (that is, not Federal) it will probably stand up to pressure better. Mine does.
If I recall correctly, the SMK 240 has the same ogive as the SMK 220 it is just longer so better sectional density and higher BC. Maybe there is a rocket scientist on here who knows better but within obvious limites I don't get too concerned about the reamer shape when it comes to bullet selection. If it shoots, shoot it. My current 300 Win Mag barrel was chambered by Bartlein using their 248 reamer. It has more than 2,000 rounds through it and shoots 230 gr Bergers and SMK 240s.
Oh ok I’ve also heard good things about the 230gr. So was your barre reamed for the 190 or 220 mk248 ? Also what kind of groups are getting out of your loads and do you happen to know what velocity your pushing ?
The barrel has an MTU profile. I told Bartlein to chamber it for 240s. If they had two reamers, I imagine that they used the 220 grain version or they used a throater and cut it long. Groups today are not so great, the barrel has about 2,500 rounds through it. I was really happy with both the 240 SMKs and the 230 Bergers. The best group it ever shot was just under 4 inches but, that was a single event, not a repeatable thing. As my skill level was improving, it was common to get under a foot. I can shoot better today. I get about 2,675 fps MV with IMR 7828, the gun really likes that. I have a keg of H1000, I should probably trot it out and try it - but I need a new barrel first.
Dunno. I have 1:9. Bullets go straight through the target at 1k. I have been reading here that faster twist is better than slower twist - so 1:8 would be better than 1:10. Read around and talk to your bullet maker.
I shoot Berger 230OTMs from a 26" 1:10 no problem. Getting 2775-2800 with Retumbo and 6+ firings on WW brass. A191 chamber.
FWIW, the mk248 mod1 shot out of my rifle back to back with the 230s hits about 10" higher at 1k and held an unbelievable waterline. Ruined every stick of brass....
Awesome glad to hear the 1:10 will handle the 230 , how much powder are you pushing ?
I am running 73.8 in blue bag WW. AGD, that load flows the brass into the ejector on the first firing. You'll have to drop back a half grain. 73.3 had the same MV in ADG and my SD was WAY lower but I can't go straight to it so I'm not sold on it yet. They both group sub MOA at 1k off a bipod and I don't shoot worth at shit at 1250. When it does hit, it hits pretty hard.
Work up. This isn't max but you never know how your stuff is going to act.
Work up. This isn't max but you never know how your stuff is going to act.
