243AI with 1-10 twist which bullet?

[dcb]

I have been doing a lot of reloading with the same barrel.
I have used mostly moly coated bullets.
Varget: 37.3 to 38gr.. lapua brass
9 1/2m rem primers
85gr sierra spitzer 2- 5shot groups 3/4" 100yrds
85gr " BTHP 10 shot group 1/2"@ 100yrds
.005" off the lands.

H4831SC 44.8grs to 47grs. 47grs most accurate
Barnes X 90gr 5- 5 shot groups measured .359" @100yrds.
also best SD velocity was 3080 to 3084f/s
9 1/2m remington primers
berger 95 gr vdl loaded .005" into the lands
velocity 3106f/s
shot 4-20 round ladders at 500 yrds with and extreme spread of 3 1/4"

shot 4-5 round groups with
100gr nosler bt's about 1" groups
75 gr hornady 6-5 shot group aver. .520" groups @100yrds

I switched over to plain bullets a few weeks ago to test some of the same loads and the weather shut me down.
First test look promising for the 85gr sierra hpbt's
shoots the lower bc bullets as good or better out to 500.
Tried some 75 grs at 1000 and only put 1 round in the target
I am going to try some speer 85gr with the 400 bc later on in the spring.
Dave

 

[Coyboy]

Heres what I got so far. 35 degrees

68gr Berger MEF <5/8 moa @ 3755fps.

85gr Sierra hpbt gamekings <1/2 moa @ 3605fps.

95gr Berger VLD >1.5 moa.

This is as far as I've gotten so far. I still need to work on a higher bc bullet. I am pleased with what this rifle is getting for both accuracy and velocity thus far.

 

[Jimm]

Hey Jim,

The 85 gr hpbt is a great performer out of either the 243 win or AI . With 10 twist I used h4350 and accuracy was in the 2's and 3's at 100. My current AI is a 7.5 twist so I'm using the 105/107/115 bullets . I see that you haven't tried the nosler 95 ballistic tip , don't be afraid to as your rifle is the final judge.

I don't think I ever shot a whitetail with the 85 gr sierra hpbt that it wasn';t down in 50 yds , mostly less . That is , shooting them through the lungs . Chris matthews is right on a s always about the " short range " part on this bullet .

Jim Brown

 

[AlbertaAl]

My pet load:
90gr Lapua Scenar @ 3435 fps with 47.7 RL19
(48.2 grains of powder was also accurate but more muzzle blast)

1:10 PacNor x 26" switch barrel on BAT with Robertson & NXS optics

 

[LRHWAL]

No personal experience with it, but you may try the 95gr SMK. BC is .480 (if I recall correctly).

Sierra told me it's optimum at 9 1/4 to 91/2 and 1:10 is marginal, but that was in 243. the AI may give you just enough extra to get you into a sweet spot.

I'd certainly try it if long range was my intention with that rifle.

 

[Tyler Kemp]

95 grain VLD, 105 grain Amax, 107 SMK all stabilize in my 6mm AI 1-10".

But, the 95 grain SMK is absolutely lights out, and shoots flatter than JBM predicts with a .5 BC. It is definitely higher than .48 at 3400 fps.

 

[Coyboy]

Well since this got dragged up from 3 years ago, I might as well update my progress since Jan 06. I was told the barrel was a Douglas originally, but after further review I'm thinking It could be Dan Liljas.

I was having some misfires with this 2nd hand rifle so after getting involved with barrel work back in 06. I cut off an inch and refit the barrel setting the Correct headspace at .004 under go. The problem was eliminated. (the old chamber was .008 over the go gauge.)

I have tried the heavier bullets with mixed results, under the right conditions I would get fair groups, different conditions egg shaped holes and patterns. This barrel is on the ragged edge with 95gr + vlds. It will shoot the 95 BT quite well.

I have pretty much stuck with the 85-87 grain bullets 3 different brands all produce 5 shot sub 1/2moa @ 100 Yards. I'm running all these bullets around the 3600 fps mark.

Thank you to the guys past and present who helped with the load info.