I can't tell a difference (9major loads)

[zzt]

clw42, why are you loading so long.  Is it because you are wary of the pressure.  A friend with a CM loads to 1.135" and uses 6.8gr WAC with a 124 for 172PF.

 

As far as plated bullets being slower, I haven't found that.  Rainier plated uses soft lead.  X-Treme uses hard lead.  Everything else being equal, if I make 173PF with Rainiers, I'll get 170 with X-Tremes and 169 with Montana Gold.

Edited December 19, 2018 by zzt

[Hi-Power Jack]

5 hours ago, clw42 said:

 RMR hp, plated, 124gr, 9mm bullets.  to 1.165.  7.4gr of WAC and I'm only at 1240FPS. 

 

That sounds awfully low for that combo.

 

I'd check Everything - starting with your chrono.   That out 10+ feet from the muzzle ?

 

I'm Major with only 6.9 gr WAC.

 

Check your scale ?

 

I'd think that plated bullets would be much higher than 1240 FPS.

[clw42]

 

19 minutes ago, Hi-Power Jack said:

That sounds awfully low for that combo. 

 

That's what I thought as well.

 

I've calibrated the scale using the weights that came with it, and that seems to check out okay.  How do I check the chrono?  It's just the Prochrono Digital.

19 minutes ago, Hi-Power Jack said:

That out 10+ feet from the muzzle ? 

 10-12' from the muzzle

 

 

I'm going to start a new thread on this in the Chrono section so I don't derail any further.  Sorry OP.

Edited December 19, 2018 by clw42

[clw42]

5 hours ago, zzt said:

clw42, why are you loading so long.  Is it because you are wary of the pressure.  A friend with a CM loads to 1.135" and uses 6.8gr WAC with a 124 for 172PF.

 

 

 

New to Major, and 1.165 appears to be  what most everyone else loads to.   Also, before I had the barrel throated I could only go to 1.08 and I was seeing some cratering on the primers with 6.7-6.9gr of WAC.  I wasn't making 165 at those lengths and charges either.  Figured I'd just go all the way out to 1.165 and up the load, however, the result is pretty much the same as far as FPS is concerned...ended up being a wash.

 

 

[zzt]

ProChrono digitals are not foolproof.  My first one read too high by 800fps.  The factory replacement was spot on.  Borrow a chrono from someone else and try again.