40gr V-Max and 12 Twist Stability

[jlc204]

I read alot about the stability issues of the 40gr V-Max (as well as other 40gr bullets) in a 12 twist barrel and I just want to give my opinion...
First, I'm not trying to discredit anybody's results that have had stability issues. By all means, if you've tried them and they go through the target sideways, yes, I beleive there is definately a problem.
However, I beleive the 40gr V-Max gets a bad reputation in more cases than is deserved.
It has been my finding that they are REALLY SENSITIVE TO SEATING DEPTHS. In general, I feel if a little more time would be spent with seating depth, there could be more shooters finding they "can" be accurate in 12 twist barrels.
Here are my consecutive targets from last summer where I kept the same powder charge for all groups, and just changed seating depth by .005 for each group. Notice the good group at 2.350 OAL, and notice how much the groups open up with just .005-.010 difference. All groups are 5 shot, except the 2.340 OAL, which was 4.
This was with a Savage 12 VLP, factory barrel.

[wirelessguy2005]

Savage seems to be the exception to the rule when it comes to the 40 grain vmax. I have had more than one Savage rifle that liked the 40 grain vmax. Other rifles I have not been so lucky with, switched over to the the 39 grain SBK and accuracy improved immediately.

[ryutzy]

It is also important to note that when a manufacturer states a given twist (1:12 or whatever) that sometimes it may actually be just over or just under that given twist. Some are just slightly faster or slower than what they are said to be. Another factor is the bore diameter may vary ever so slightly and these two mentioned factors can be the deal makers or breakers when it comes to bullet stability with a bullet that is said to be "on the edge of stability" in a given twist. Just like the 40 grainers in a 1:12 Hope that all makes sense.

[Sth Oz Dan]

Thanks for the pics jlc.

A good illustration of the effects of seating depth on consistency.

[jlc204]

Your welcome, I just wanted to tell people not to give up on the 40gr v-max's too early without giving them a fair shake. It took quite a bit of load testing before I achieved accuracy. (Some of which was a learning curve on my part)
Will it shoot that load into .25" 5 shot groups all the time? No, but I can say it will keep 5 shots under .5". I don't think you can ask for much more than that out of a factory barrel.

[Jim White]

My CZ will shoot 40 VMAX's but the Remingtons of mine, it's a no-go. I tried different powders, primers and seating depths...no good. A shame too because the VMAX's are a pretty good deal compared to the Sierra's. IMC, it has to be the barrels because the bearing surface between a 39 SBK and a H VMAX isn't that much difference, AIRC.

[bow shot]

My savage did very well with them!