95 Matchking .224

[xswanted]

What twist are people using for these?

Does a 7 stabilize them well enough to get the full BC out of them?

 

[Jdne5b]

7 wont get full BC (at .223/FTR speeds) but will shoot them accurately.

 

[linebaugh]

At 3000 fps I am getting above advertised BC to 900 yards with a 7 twist. It begins to falter rather rapidly beyond that. First shoot with that combo today so we shall see how it does. Longest shots 1000 yards today but I have shot 1250 and 1500 with that combo to get my drop data trued up.

 

[Ned Ludd]

As has been noted, a 7-twist may or may not generate the full intrinsic BC of the 95 SMKs depending on velocity, elevation, temperature, etc. Much better to use 1.270" as the bullet OAL and play around with the other various input values yourself to see what will work where you shoot most often.

https://bergerbullets.com/twist-rate-calculator/

 

[xswanted]

Thank you guys.

Looking at using a larger case than 223 and running them 2950ish

 

[xswanted]

At 3000 fps I am getting above advertised BC to 900 yards with a 7 twist. It begins to falter rather rapidly beyond that. First shoot with that combo today so we shall see how it does. Longest shots 1000 yards today but I have shot 1250 and 1500 with that combo to get my drop data trued up.

Any issues with the jackets coming apart?

 

[linebaugh]

Any issues with the jackets coming apart?

None so far. Keep in mind with 7 twist @3k I am probably slightly underspun so if I was to have problems you would have a bullet that was technically un-usable. If you have them coming apart before they make it to a full inteinsic BC you have issues.

Keep an eye on the carbon build up in your throat area. I am reasonably convinced that overbore small calibers with these heavies build the carbon up in a hurry. Nothing routine cleaning can't keep ahead of but just faster than I notice in other caliber configurations.

 

[Evan]

At 3000 fps I am getting above advertised BC to 900 yards with a 7 twist. It begins to falter rather rapidly beyond that. First shoot with that combo today so we shall see how it does. Longest shots 1000 yards today but I have shot 1250 and 1500 with that combo to get my drop data trued up.

What are you using to propel them along at 3k? I've got a 7 twist 22BR being made and was contemplating trying these out. I'm a little nervous that I'm going to be blowing up bullets but I figure that I'll just clean often and not let the gun or ammo get very hot. Oh and also not run it up to the ragged edge of pressure and speed.

 

[linebaugh]

What are you using to propel them along at 3k? I've got a 7 twist 22BR being made and was contemplating trying these out. I'm a little nervous that I'm going to be blowing up bullets but I figure that I'll just clean often and not let the gun or ammo get very hot. Oh and also not run it up to the ragged edge of pressure and speed.

30" tube. 7 twist bartlein. 22BR plus .050 blown out shoulder so about the capacity of BRA perhaps a touch more. My bbl has a deep throat to get those bullets out to the neck shoulder juncture. Running N160 and 3,000 fps at 75 degrees. Actually going to be a bit more when it gets in real heat. No pressure issues noted yet. 3 loadings on some brass with tight primer pockets.
So at 1200 elevation that I typically shoot by bergers estimate I am 2% short of stable. It's a computer program so who knows if it's an exact science. That said if you blow bullets at a less than stable spin the bullets become worthless. I need to check my notes but I assume I am in the 500 round range and no problems whatsoever except the bc seems to drop off more rapidly after 1000 yards.