Best jacketed 9mm for the $

[IDescribe]

PD at $89/1000 shipped to your door for 124gr JHP is getting it into plated price ranges but for a much better bullet, and you only have to buy 2000 to get that price, as opposed to the full case of MG. That's the big difference.

[v1911]

I suppose it depends on the quantities ordered, but for my needs, PD has always been more economical than MG.

That being said, I normally run coated.

[noylj]

Want a jacketed practice bullet?

I find PD is more thsn good enough for match shooting.

[JimF38sup]

If you are shooting open only bullets with no lead base unless you like cleaning the comp. I've used Hornady FMJ 115 good bullet lots of lead in the comp.

MG 121 IFP at 175 power factor tears in the target (not round holes)

Zero 124 FMJ good bullet but comp lead.

Now Precision Delta 124 JHP no complaints so far, just ordered 5k more

[Hi-Power Jack]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

[outerlimits]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

[IDescribe]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

The lead and coated lead bullets obturate better and faster, and they're typically sized larger, so they let less gas slip buy, and pressure builds faster and higher than an equivalent charge with a jacketed bullet.

[outerlimits]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

The lead and coated lead bullets obturate better and faster, and they're typically sized larger, so they let less gas slip buy, and pressure builds faster and higher than an equivalent charge with a jacketed bullet.

Tested the size theory and it does not prove to be true.

[jrswanson1]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

Less friction with lead and crayon versus copper.

[IDescribe]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

The lead and coated lead bullets obturate better and faster, and they're typically sized larger, so they let less gas slip buy, and pressure builds faster and higher than an equivalent charge with a jacketed bullet.

Tested the size theory and it does not prove to be true.

Tested size theory? How?

[IDescribe]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

Less friction with lead and crayon versus copper.

There is undoubtedly less friction, but that is not the dominant factor in why you need less powder with lead than with jacketed to reach the same velocity. While the hypothesis that less friction would allow the bullet to accelerate faster with less force -- while that hypothesis does track logically, and that dynamic certainly exists, the reduction in pressures you get from faster acceleration means that lead bullets should have charge windows up to SAAMI max standard pressure that were HIGHER than jacketed bullets, but they're not. They're lower. Velocity is not the limiting factor in load windows -- pressure is. So when you see lead bullets with lighter charge windows than jacketed bullets, THAT means that lead bullets are getting higher pressures than jacketed bullets at the same charge weight. The reduced friction you cite is in play, but it is outweighed by the better obturation of the lead bullet doing a better job of containing the gases and building pressure faster.

If you'd like an example of things moving in the other direction, some benchrest guys coat their bullets and barrels in hexagonal boron nitride to decrease friction. But the reduced friction of the coated bullet doesn't get them extra velocity. They actually lose velocity. They have to increase powder a little to get back up to the same velocity they had with the uncoated bullet. Like so many things with reloading, there are positive and negative influences with any given factor. Lead bullets have less friction than copper and would accelerate faster for sure, but that doesn't mean they get to a higher overall velocity since that faster acceleration weakens the pressure curve. Better obturation, however, strengthens the pressure curve, and since we can see by comparing charge windows in published load data that lead bullets generally hit SAAMI max standard pressure with LESS powder than jacketed bullets, we can assume that between obturation and friction, obturation is the stronger factor.

[IDescribe]

Here's another factor that affects internal ballistics people may be familiar with that may help them see what's going on: loading into the lands.

Smokeless powder burns faster the more pressure it's under, and the more pressure it's under, the faster it burns. It's a positive feedback loop and a geometric progression. So anything you do at the beginning of the burn to increase pressure has an ever-increasing effect through to the peak. If you shorten OAL, pressure goes up because the reduced initial size of the combustion chamber increases initial pressure. It's one of the reasons we shouldn't take a known load and just reduce OAL to get it to fit our pistol, unless we lower charge weight and work back up. Most of us know this. And it works in the same in the opposite direction. If you start with an especially short OAL, and start to increase it, as you increase OAL and increase the size of the combustion chamber, pressures decrease. But that actually stops when you get the OAL long enough to strongly engage the lands of the rifling. Shorter than that engagement point, when you ignite the powder, the bullet starts to accelerate from zero and builds momentum with very little pressure, then its rate of acceleration experiences a hitch as the bullet hits the rifling, but pressure gets an assist from momentum, which helps minimize that hitch and carry the bullet into the rifling where it continues to accelerate steadily. The momentum allows the bullet to pass into the rifling under less pressure than if the bullet had no momentum at all. However, when the OAL is long enough to engage the lands/rifling, it never gets that little bit of momentum going to help it pass into the rifling, and pressure has to get much higher before the bullet ever moves. This delay in the expansion of the combustion chamber has a significant effect: pressure is much higher at the moment the combustion chamber starts to expand, and that increase in pressure will grow geometrically as pressures increase, strengthening the pressure curve, and increasing peak pressures and overall velocity.

These are the principles in play. And these principles play out in a converse fashion when there is a decrease in friction: there is a faster initial rate of acceleration, and thus a faster initial expansion of the combustion chamber, which lowers the rate of pressure increase, and weakens the pressure curve enough that you end up with a lower velocity overall. The weakening of pressure throughout the burn outweighs the increase in acceleration you get from the lower friction.

[L3324temp]

I've never rd used these but the price seems right.

https://rmrbullets.com/shop/bullets-for-reloading/bullets-for-reloading-9mm-355-12/9mm-115-gr-fmj-rn-new/

[outerlimits]

Powders I have in stock are TG and CFE Pistol. Do I just follow the standard lead recipe?

You'll need more powder to get a jacketed bullet to the same velocity as a lead bullet.

That is true. But I've Never heard an explanation as to why.

Less friction with lead and crayon versus copper.

There is undoubtedly less friction, but that is not the dominant factor in why you need less powder with lead than with jacketed to reach the same velocity. While the hypothesis that less friction would allow the bullet to accelerate faster with less force -- while that hypothesis does track logically, and that dynamic certainly exists, the reduction in pressures you get from faster acceleration means that lead bullets should have charge windows up to SAAMI max standard pressure that were HIGHER than jacketed bullets, but they're not. They're lower. Velocity is not the limiting factor in load windows -- pressure is. So when you see lead bullets with lighter charge windows than jacketed bullets, THAT means that lead bullets are getting higher pressures than jacketed bullets at the same charge weight. The reduced friction you cite is in play, but it is outweighed by the better obturation of the lead bullet doing a better job of containing the gases and building pressure faster.

If you'd like an example of things moving in the other direction, some benchrest guys coat their bullets and barrels in hexagonal boron nitride to decrease friction. But the reduced friction of the coated bullet doesn't get them extra velocity. They actually lose velocity. They have to increase powder a little to get back up to the same velocity they had with the uncoated bullet. Like so many things with reloading, there are positive and negative influences with any given factor. Lead bullets have less friction than copper and would accelerate faster for sure, but that doesn't mean they get to a higher overall velocity since that faster acceleration weakens the pressure curve. Better obturation, however, strengthens the pressure curve, and since we can see by comparing charge windows in published load data that lead bullets generally hit SAAMI max standard pressure with LESS powder than jacketed bullets, we can assume that between obturation and friction, obturation is the stronger factor.

thanx fer the explanations. sounds credible.