when 7/10th'sof a grain only bumps up 50fps

[ProGunGuy]

what does that tell you

I have been experimenting with ramshot comp powder. I started with 3.2 gr and then 3.5/3.7/3.9. this is with a 124gr MG jhp. this was shot out of my 4" mp9. the difference between the lightest charge and the heaviest charge only netted me about 50fps more.

So what am i looking at? why so little gain in FPS. ramshot comp is supposed to be a fast powder comparable to VV320.

also for those that use the lee auto disk, the ramshot comp threw the same amount as listed for vv320

thanks

[yoshidaex]

Not 100% certain but when your velocity starts leveling off when increasing powder charge, you're close to danger territory.

[ProGunGuy]

Not 100% certain but when your velocity starts leveling off when increasing powder charge, you're close to danger territory.

I read the tea leaves, aka primers and non of them even remotely looked like they were starting to flatten. I resized a few of the fired cases and they resized easy.

[CocoBolo]

Not 100% certain but when your velocity starts leveling off when increasing powder charge, you're close to danger territory.

My expierence as well. Went there with TruBlue 7.9 to 8.3 not much fps then 8.5 primer punch thru, ruptured cases. No real damage just annonying.

Looking at the load data for Comp with 124gr JHP (hornady xtp) max load is 3.0. Of note is the very short OAL 1.060. Comp was on my todo list someday when I start playing the minor game again so I'd like to know the answer. You probably have a long OAL it takes a bit more powder and MTG is harder to push than a Hornady or Zero. Make sure you are using minimal crimp you can lose 60 fps with too much crimp. You are out there on your own beyond the charts, so be cautious.

[FightFireJay]

When I was in the paintball industry I would tune some paintball guns (or paintball markers, depending on how PC you want to be) using a similar system. I would increase the pressure of the compressed air (and reduce the pressure of the spring that pushed the hammer that struck the valve to open it) until I found that an increase in pressure actually kept the valve slightly closed and didn't result in an increase in velocity. End result?... extremely consistent velocity (and never any velocity spikes that could cause penalties during a tournament).

So long as you are not over pressure for the caliber... I should think you could do the same thing, resulting in a very consistent velocity. It may be that the extra powder is actually "getting in the way of" the flame front and slowing down the ignition of the powder.

(such are the ramblings of a man to intoxicated to reload so he gives advice to others.... take with grain of salt because YMMV and for those of you that are members of advrider.com, FYYFF!)

[Sarge]

Powders will "plateau" or "hit a wall" from my experience as well. Like Coco and others said, I have loaded some 9MAJOR rounds with a given load of powder X and tried to get a little more gas by bumping the load and found that velocities increased very little if at all, SD's started getting less desirable, etc. Primers get flatter and no more gas really to speak of.

[ProGunGuy]

Not 100% certain but when your velocity starts leveling off when increasing powder charge, you're close to danger territory.

My expierence as well. Went there with TruBlue 7.9 to 8.3 not much fps then 8.5 primer punch thru, ruptured cases. No real damage just annonying.

Looking at the load data for Comp with 124gr JHP (hornady xtp) max load is 3.0. Of note is the very short OAL 1.060. Comp was on my todo list someday when I start playing the minor game again so I'd like to know the answer. You probably have a long OAL it takes a bit more powder and MTG is harder to push than a Hornady or Zero. Make sure you are using minimal crimp you can lose 60 fps with too much crimp. You are out there on your own beyond the charts, so be cautious.

3.2 got me about 830fps. it did cycle the mp with no problems.

[67ls7vert]

So, Are you saying that the powder is starting to hit the maxiumum velocity (the Wall)?