How does this happen???

[CMB]

Just did a little testing....

55 grain Ver.4 with 23.5, 24, 24.5, 25, 25.5 and 26 grains of X-Term @ 2.260. The 23.5 through 25.5 all shot exactly the same. I couldn't believe it - all under an inch. Of course I'll load @ 23.5 to conserve resources. Each charge was hand measured on a 505 then cases labeled with a sharpie. The only thing different this time was instead of resting on a bipod, this time I was on a bag rest.

All loads the same ‐ how often does this happen? Has anyone else experienced this?

 

[Metal God]

In all actuality they probably don’t you just lucked out and all the variables stacked up in your favor in that run . Go ahead with your 23.5 but I’d also take another load out there at 24.5 or 25 and see if they still shoot exactly the same this time . Do10 round groups or two groups of five with each

 

[iShoot17]

As for the conserving resources - did you run these over a chronograph? Check ES and SD?

While we don’t know your intentions, these variables may play a role in your adventure. Potentially to the point of using that one extra grain of powder worth it. (Let’s be honest here - the difference in 23.5 or 24.5 is a difference of 12 rounds per pound.)

An example would be if you plan to shoot further distances, where a little more speed and less SD and ES (if that’s the case) could be beneficial.

 

[NR53]

I've had very good luck with X term and 55 grain bullets in 223/5.56. Looks like you have too. I settled on 24.2 gr. and OAL of 2.250

 

[CMB]

I wish I could have measured the velocity of these. I guess it's time for a crono. Usually while testing I can watch the group close then open then close again. It was a beautiful sunny 58 degree day. After each group im thinking to myself this can't be happening....

This definitely warrants a retest as suggested with 10 shot groups. Now I just need to wait on the same weather.