Powders for 9mm pistol caliber carbine

[Timmis2]

I recently worked up a load from Hodgdon data for the 65gr Inceptor ARX projectile 9mm with CFE Pistol powder and tested it in my Ruger pistol caliber carbine 9mm through my chronograph. I am getting 350 FPS more velocity than the maximum load in the data with the same COL and amount of powder (7.3 grains CFE Pistol) which I attest to the barrel being 12 inches longer. The Ruger performed flawlessly with no signs of overpressure from the gun or the case and primer.

There are 7 other powders to choose from in the data for this projectile. What's interesting to me is of the 7, one powder at maximum load (Winchester 572) is 90 FPS slower, used 1.2 grains more, but is 4500 PSI less pressure (28500 PSI) than CFE Pistol (33,000 PSI) which I assume might have something to do with it being a slower burning powder according to the burn rate chart. I have read that slow burning powders can be ideal for longer barrels because the slower burn builds velocity as the projectile is exiting the barrel.

If I followed the data loading 572 to compare, how likely is it that I may see a gain in velocity greater than what I got from CFE Pistol due to the slower burning powder with a longer barrel? This interests me too because the lower pressure with 572 may afford to work up further than the published maximum load since the pressure is significantly lower, nearly 10,000 PSI less than +P loads (the Ruger PC Carbine is rated for +P). One thing to be cautious of is case capacity. The maximum load data with 572 is 8.5 grains. I do not want to compress the powder with the projectile. I do not know how much case capacity is left with 8.5 grains of 572 and don't want unforeseen pressure spikes.

 

[SeabeeKen]

ANY pistol powder you use will be burnt up before the bullet exits your rifle barrel. I would test and see which is more accurate. You may not be able to get enough 572 in that puny case to get the pressures up. Accuracy hits targets, not speed. Low pressure may not seal the case against the chamber wall. Its a small case in a rifle, it is what it is.
The 350 Legend might be more suited for your rifle

 

[Hoser]

A slow powder like 572 will give you a higher velocity in a longer barrel. In a short barrel lots of the powder gets burned outside, in a long barrel you get to burn it all in the barrel.

Compressing 572 isnt a big deal. Stick to the OAL that Hodgdon has listed and you will be fine.

For a while I played with Blue Dot, N350 and N105 with 135gn bullets in a 10mm carbine. I got some screaming high velocities that were fun and accurate.

 

[dellet]

Slower powders creating higher velocities can be true, but honestly it’s become more of an internet myth than reality. There is a whole set of factors that need to align. Your example load is a good one. It’s also a good reason to suggest if you’re interested in this type of load work up, that you explore Quicklooad or Gordon’s.

A Quick Look at Hodgdon data for the two powders tells me it’s not likely to work as you hope. The reason being the load is maxed out, but pressure is well below maximum. Next clue is 572 is not listed for a +P load. That’s a good indication the powder is maxed out for performance already.

In general, powder producing the highest velocity in a short barrel, will also produce the highest velocity in a longer barrel. As long as you’re comparing pistol to pistol, rifle to rifle. When you start comparing pistol to rifle, all bets are off. Adding 12” of barrel is likely to have different results starting with 4”, 10”, 16”. Shooting the same load in 4” barrel may not stop gaining velocity and actually start slowing down until you shoot it in a 26” barrel. This is where the “It Depends” clause takes effect.

If you look at your load, 65 grain bullet, 572 and CFE Pistol, there is a curios set of data. Hodgdon left a huge amount of potential pressure and velocity on the loading bench. So either they did not try a compressed load, or didn’t indicate it. Both are not uncommon.

The curious part is that if you look at the same two powders with a 90 grain bullet at max pressure, they have the same pressure, but 572 has more velocity. This brings up the other factors I mentioned before.

Smokeless powder needs pressure to burn correctly, better stated burn as designed, to achieve a certain pressure curve. That pressure comes from the bullets resistance to sliding down the barrel. Bullet construction is the key here. Material, bearing surface, weight are the key factors. It’s probably pretty safe to 572 needs more resistance to develop the pressure to burn correctly. That’s why less powder pushing a heavier bullet develops more pressure.

Bottom line, an educated guess, 572 vs CFE pistol with a 65 grain bullet. CFE still has the higher velocity in a 16” barrel.
Change that to a 90-100 grain bullet and 572 may very well have the velocity advantage.

Probably the only thing to gain with 572 and a longer barrel is carbon build up. An inefficient burn due to lack of pressure just gets worse the longer the barrel is. That’s what you have with 572 and a 65 grain bullet.

 

[Timmis2]

Slower powders creating higher velocities can be true, but honestly it’s become more of an internet myth than reality. There is a whole set of factors that need to align. Your example load is a good one. It’s also a good reason to suggest if you’re interested in this type of load work up, that you explore Quicklooad or Gordon’s.

A Quick Look at Hodgdon data for the two powders tells me it’s not likely to work as you hope. The reason being the load is maxed out, but pressure is well below maximum. Next clue is 572 is not listed for a +P load. That’s a good indication the powder is maxed out for performance already.

In general, powder producing the highest velocity in a short barrel, will also produce the highest velocity in a longer barrel. As long as you’re comparing pistol to pistol, rifle to rifle. When you start comparing pistol to rifle, all bets are off. Adding 12” of barrel is likely to have different results starting with 4”, 10”, 16”. Shooting the same load in 4” barrel may not stop gaining velocity and actually start slowing down until you shoot it in a 26” barrel. This is where the “It Depends” clause takes effect.

If you look at your load, 65 grain bullet, 572 and CFE Pistol, there is a curios set of data. Hodgdon left a huge amount of potential pressure and velocity on the loading bench. So either they did not try a compressed load, or didn’t indicate it. Both are not uncommon.

The curious part is that if you look at the same two powders with a 90 grain bullet at max pressure, they have the same pressure, but 572 has more velocity. This brings up the other factors I mentioned before.

Smokeless powder needs pressure to burn correctly, better stated burn as designed, to achieve a certain pressure curve. That pressure comes from the bullets resistance to sliding down the barrel. Bullet construction is the key here. Material, bearing surface, weight are the key factors. It’s probably pretty safe to 572 needs more resistance to develop the pressure to burn correctly. That’s why less powder pushing a heavier bullet develops more pressure.

Bottom line, an educated guess, 572 vs CFE pistol with a 65 grain bullet. CFE still has the higher velocity in a 16” barrel.
Change that to a 90-100 grain bullet and 572 may very well have the velocity advantage.

Probably the only thing to gain with 572 and a longer barrel is carbon build up. An inefficient burn due to lack of pressure just gets worse the longer the barrel is. That’s what you have with 572 and a 65 grain bullet.

Thank you for that insight. Of the 7 other powders in the Hodgdon Data, do any of them seem worthy to you for greater velocity gain than CFE Pistol produced? There was a similar test done by another person with the same bullet and 16 inch barrel in an AR9 (blowback) using AutoComp. The person worked up 1 grain above maximum load but only increased velocity by 200 FPS greater (2250 FPS average) than my results with CFE Pistol at maximum load and began seeing primer cratering and pressures possibly exceeding +P. That juice isn't really worth the squeeze to me. Another question..would switching to small rifle magnum primers when working up above maximum published loads have advantages in this example? I would think no with fast burning pistol powder, but possibly yes with a slower powder like 572.

 

[Jerry Snyder]

N 320 works for me in 9mm, 40sw, and 45acp

 

[dellet]

Way too much there for an easy answer. This is exactly why you need some sort of calculator. You then have the tools to run models of multiple powders.
If you’re chasing velocity, powders come in two basic groups. Ones that you can’t fit enough in the case to achieve the velocity you hope for, and those that create more pressure than is safe before you get that same velocity. There is a small intersection of these two groups where you settle to work on accuracy and in the case of an Auto loader, reliability.

With that said, let’s work off the cuff and see how much trouble we can cause. Some Specific questions answered above, might lead you to a new strateegery.

Thank you for that insight. Of the 7 other powders in the Hodgdon Data, do any of them seem worthy to you for greater velocity gain than CFE Pistol produced? There was a similar test done by another person with the same bullet and 16 inch barrel in an AR9 (blowback) using AutoComp.

This is exactly where you would use a program like Gordon’s or Quickload. Enter the loads, change the barrel length and compare the models. It’s still speculation, but it’s an educated and mathematical solution, not a wild as guess based on probability.

The person worked up 1 grain above maximum load but only increased velocity by 200 FPS greater (2250 FPS average) than my results with CFE Pistol at maximum load and began seeing primer cratering and pressures possibly exceeding +P. That juice isn't really worth the squeeze to me.

Way too many unknowns. If this person has a lot of experience with a certain powder and cartridge, he probably was able to keep himself safe. Same load in another rifle or pistol could easily be a disaster. Reading pistol primers as a pressure sign, without knowing the exact primer and commenting on safety, is probably one of the dumbest things a person could do. Remington 1 1/2’s is a good example because they put the warning on the label. “Don’t use these in high pressure cartridges” then lists examples. You can start seeing problems well below 35,000 psi. They are a great primer to use in weak actions. Plenty of early warning signs. Flip side is a small pistol magnum primer, you can load to 45-50,000 psi and not get a crater and still have rounded edges depending on the bolt face.

Another question..would switching to small rifle magnum primers when working up above maximum published loads have advantages in this example? I would think no with fast burning pistol powder, but possibly yes with a slower powder like 572.

The advantage of using a small rifle magnum primer would be that your first sign of excessive pressure could be a blown primer pocket or mechanical failure of the firearm. You can shoot a dangerous load in confidence and share that load on the internet telling everyone check out my 60,000 psi load that doesn’t flatten primers. Don’t worry, it’s +P (38,500) rated action.

Then again the above statement is also misleading because there are plenty of pistol cartridges that use a small rifle magnum primer. And a few rifle cartridges that recommend pistol primers.

Bottom line is that when you start going to these extremes to gain a couple hundred fps in velocity, it time to move onto a different cartridge. Or at least a different bullet.

A 300 fps increase in velocity, 2000- 2300, with a 65 grain bullet nets about 200 pounds of energy. 575 to 775

A 25 grain increase in bullet weight at 2000 fps is 800 pounds.

Again the models generated with a loading program will help sort this out. Lots to look at.