9mm bullet weight for USPSA

[DIYguy]

Just now making the jump into reloading and the complete set up for the Hornady LNL AP press. Pushed a $1,300 cart out of Cabela's over the weekend.
As I'm looking at the different recipes I'm wondering which is better for USPSA shooting in the Production division.
Lighter bullet, higher velocity or heavier bullet at lower velocity?
Stock rounds have always been 115gr in the 1,200+ range but if I'm loading my own, is it better to go 147gr and around 950?
124gr @ 1,180?
Pros and cons?

 

[growr]

All steel is calibrated to fall with a 115 grn FMJ factory round. You can either replicate that or try to improve with a heavier bullet and see what happens....the paper doesn't care.

Heavier bullets will impact higher than a 115 will however.

Were it me, I would start with replicating a factory round first and then branch out.

Randy

 

[greenmachine]

Quote: "Heavier bullets will impact higher than a 115 will however."

This is why I've mostly gone to 147's.

 

[Bkreutz]

It's all personal preference, I've tried most, if not all, the combinations (including 135 and 160). I've settled on 124/125 because it feels the best for me.

 

[AzShooter]

Try 147s I think you will find that they recoil less by feel.

 

[Jim Watson]

Stock rounds have always been 115gr in the 1,200+ range but if I'm loading my own, is it better to go 147gr and around 950?
124gr @ 1,180?

In the first place, you don't need to load that hot.
Production's Minor Power factor is 125, allow 130 for safety margin and get a 115 at 1130, a 124 at 1050, or a 147 at 885.

A slow heavy bullet will have less FELT recoil.
While I like the 147, I am comfortable enough with a 125 which is subsonic and spares me the sharp CRACK! of a 115. And lead is cheaper than powder.
Right now I am loading 135s in order to get the roundnose shape I need from my vendor.

 

[fredj338]

Most of the guys I know that are really into USPSA or IDPA, shooting 9mm minor, are using heavy 147-160gr bullets going slow. REcoil is stupid soft & it's easier to get to minor & still have 100% reliable functioning. I feel torque, induced by higher vel, is part of the recoil issue. A 160gr bullet @ 800fps vs a 115gr @ 1150fps, just feels softer & more linear recoil, a push vs a snap. I'm sure someone more math savvy can do the RPM on that.

 

[S&WIowegan]

I load Bayou Bullets' 124 LRN to about 1100 fps. I like the way they feel in 1911, Glock, M&P and XDm. If I use factory it's always cheap 115s but they are loud.

 

[DIYguy]

This is exactly the info I was looking for. I had read that heavier bullet, lower velocity but still making PF has less recoil.
Do want to make sure the PF can still tip the steel silhouettes. Last week had one guy rang the steel three time and not tip. Match stopped as army of ROs checking the silhouette for malfunction.
Could be wrong but I'm thinking the heavier bullet even at lower velocity will have equal or greater tipping power.

 

[DIYguy]

Variation on the same question but 40 cal.
I also shoot my M&P 40 but not as much as the 9. The 40 has more of a kick and crack than my 1911 45 does and I expect it is the difference in subsonic vs supersonic rounds.
If I load up 180 gr bullets at around 6 grains of BE-86 I'm guessing I should be around the 950 +/- fps range. This would get me into the Major class for Limited if I use that gun (looking at some mods but different thread)
I haven't shot 40 cal rounds in this configuration but hoping this would have a softer feel than the standard 165 gr @ 1,150 with less "crack".
Is this correct?

 

[WR Moore]

What knocks steel over is momentum. Bullet weight times velocity. Doesn't matter what the bullet weight is, so long as you have the momentum.

Subjective recoil is another matter. 147 @ 860 will give you minor. So will 125 @1000, or 115 @ 1050/1100. I happen to like 115 @ 1150.

In .40, if you're going heavy you might want to consider 200 gr. @ 830-840 f/s for major.

 

[roundgun]

I am currently in the process of reloading some 135 grainers and have been collecting point of impact and velocity data. I also noticed a higher point of impact than the factory 115 grain winchesters. What's the physics behind this?! I would think the heavier bullet would be effected by gravity more and impact lower on the target.

 

[DIYguy]

I just spent two hours at the range last night (Friday) with multiple boxes of 40c ammo, different manufactures, different bullet weights.
All of the 165 gr 40c hit low. Depending on manufacturer, two to three inches low.
At 25'+ the 180 gr hit on line or slightly high (same sight picture)
I was at the range killing time and ammo waiting for my gunsmith to finish the new FO front sights and Apex upgrades to my M&P9.
I've had issues with the 40c before being low and left and my LGS GS knew about the issues so we talked about ammo difference. He stated 40c does not like 165 gr and shoots better at 180 and 200. He said 165 shoots low. Looking at the stack of calibration targets he agreed, shoot 180 gr and we need to push the rear sights right, their off.
Moral of story (do not know why) heavier grain bullets have a higher POI
Now for the physics class for those than can explain ???

 

[Bkreutz]

The theory that I've heard is that the heavier bullet is slower to accelerate allowing the barrel to rise a bit more (a very little bit more) before the bullet leaves the barrel. Makes about as much sense as anything else I've heard. It wouldn't take much of a difference.

 

[fredj338]

The theory that I've heard is that the heavier bullet is slower to accelerate allowing the barrel to rise a bit more (a very little bit more) before the bullet leaves the barrel. Makes about as much sense as anything else I've heard. It wouldn't take much of a difference.

Barrel time is a nice theory, but easily disproved. At say 25yds, 200r 45 vs 300gr 45, both running 800fps, same bbl time. The 300gr will shoot higher. I have never had a lighter bullet, any caliber, shoot higher than a heavier bullet at normal handgun ranges of 25yds & under.

 

[fredj338]

What knocks steel over is momentum. Bullet weight times velocity. Doesn't matter what the bullet weight is, so long as you have the momentum.

Subjective recoil is another matter. 147 @ 860 will give you minor. So will 125 @1000, or 115 @ 1050/1100. I happen to like 115 @ 1150.

In .40, if you're going heavy you might want to consider 200 gr. @ 830-840 f/s for major.

I shot met sil for awhile, it is about bullet wt as that is major component of momentum. Easier to get weight up vs vel. The other issue on steel is the amount of time the bullet stays on the plate to deliver the momentum. A 90gr bullet @ 1300fps has the same momentum as a 147gr @ 800fps. The 147gr will push on the plate longer, assuring momentum transfer.

 

[H Richard]

If you ever get the chance to watch slow motion of a bullet hitting metal do it. The lighter bullet at high velocity has a much higher probability to "shatter" into many small pieces and evaporate off the surface of the metal, and the heavy slower projectile will collapse into itself (smash) and stay in contact with the metal longer which results in more momentum to knock the target down.

 

[waynet]

If 47% of the competitors in production division (9mm only) use 147gr bullets, there must be a good reason.

2016 Nationals Survey Results

 

[Thomas15]

Most of the guys I know that are really into USPSA or IDPA, shooting 9mm minor, are using heavy 147-160gr bullets going slow. REcoil is stupid soft & it's easier to get to minor & still have 100% reliable functioning. I feel torque, induced by higher vel, is part of the recoil issue. A 160gr bullet @ 800fps vs a 115gr @ 1150fps, just feels softer & more linear recoil, a push vs a snap. I'm sure someone more math savvy can do the RPM on that.

This has been my experience also. Having said that try a few variations and see what works best for you. But in the end you will be using something heavier than 115g.

 

[Thomas15]

oopse.. old thread