Sierra 230 MK #2251

[Ackley Kid]

Has anyone had any luck with new 230s ? Could you please indicate cartridge and twist rate you are using . Thanks !

 

[Ackley Kid]

Ran these through the Berger Twist rate Calculator with a length of 1.754 supplied by one of the Sierra techs and 9 twist . Calculator came back with SG of 1.5 at 2800MV @ 59F @ 800FT above sea level ( home range ) . Has anyone had success with a 9 twist ? I know Sierra’s recommendation is 8 twist or faster ...I had plans of trying them in 300 WSM / F Class rifle . Most had indicated that .280FB would work so if these don’t pan out , 230 Hybrids can be utilized as well . Still looking for real world results with 230MK .

 

[gilmillan1]

I tried then in a 9.5t and they were not very accurate. Hybrids were much more accurate. Sierras shot a tiny hole at 100 but not consistent at 600 yards. I gave up on them on this barrel. Maybe they do need an 8t. Dont know. I shot about 300 of them. I think it's worth working on them but you need an 8t.

 

[Ackley Kid]

9.5 twist shows 1.34 SG . I’m not sure if 9 is going to be much better , won’t know till I try ? Like you said , an 8 might be required but not likely to find one here in Canada . Definitely would have to order one up and wait . Just curious on results from others as I have shot the Sierra 183 / 7mm out of a 8.5 twist / 5R with good results . Guys here are having decent results with 9 twist barrels as well so thought the same might boil over into the 30 cal offerings . New MK bullets are much harder to tune than hybrids ECT , and nodes are some what narrow from my experience ( used 183 for two seasons ) . A few are using the 200MK in 10 twist here and report good things , but not sure of elevation where they are shooting them ? Thank you for your post greatly appreciated.

 

[FrankG]

My F open gun is in .300PRC. I'm slinging 225's and 230's at a honest 2900fps. and I'm not stepping on it either. Barrel is a 1-9 twist. They held 1/4moa for vertical at a 1k yards. No issues. Shot them at 800 and 900 as well the same day. Temp was 60 degrees or so. Elevation is about 820 feet. At my house it's just over 600 feet but I can only shoot out to 430 yards at my house.

According to my twist calc's at 2800fps. they need like a 1-9.52 min. At 3000fps. you need something like 1-9.24. If memory serves me right.

My very first loads thru the new barrel was right at 2800fps and they shot fine but was all short range testing.

The bullets I have measure around 1.740" for length.

The 225 Hornady's shot great. Shot them in the same test/same day with the SMK at 800,900 and 1K. In all honesty it would be hard to pick one over the other.

Later, Frank
Bartlein Barrels

 

[FrankG]

From the line to the target...the bullets according to the Silver Mtn. target system where hitting the target at 1890-1900fps. from a 1k yards out.

My come ups where 16 min. from a 100 to 800, 19.375 to 900 yards and 22 min. at a 1k for some numbers for ya.

 

[Ackley Kid]

Frank good to know on the 1.740 as I don’t have any on hand . I have a 9 twist enroute I’m going to try in a 280fb WSM . Wow those things shoot pretty flat 22 min ! Thanks for your post appreciate the info .