Sanity Check - 9mm Glock 43 125g at 1255fps

[TundraTim]

Hello all, I need a sanity check. I've got a 125g JHP load that shoots 1255fps in a Glock 43. I've also tested it in a Glock 26 and got 1267fps. I was surprised with how fast it is. I'm using load data from Lee. Here's the load info.

125g Sierra JHP #8125. New Troy brass. 6.6g of Power Pistol. OCL 1.130. Lee factory crimp die, set to 3/4. Each powder drop was weighed.

The load data shows 1235fps and I'm getting 1255fps in a 3.41 inch barrel. The only error I've identified so far is that the Lee data calls for minimum OCL of 1.150 and for whatever reason is used 1.130 by mistake. I plan on retesting with the OCL at 1.150 but I thought I'd ask in case there's something else that I might be missing, I can't imagine that the OCL would make a big difference in velocity.

I'm not seeing any signs of over pressure, the spent casings show a little resistance when inserting in the barrel after cleaning it. Of course the recoil is very strong and sharp, similar to the Underwood 115g +P+.

As a reference point, I'm getting 1292fps with the Underwood 115g +P+ ammo in the same gun (G43).

Aside from the OCL, am I missing something?

Thank you in advance.

 

[steve210]

That's a lot of powder( power pistol) sounds like too me. My standard load is 5.0 gr. Of power pistol with a 124 gr. Bullet. Plinking load but definately not a pooch load.

 

[stavey]

From what I understand . Troy brass may use stepped brass . In order to use less powder. Be careful.

 

[243winxb]

https://sierrabullets.com/load-data/ Chronograph velocity error?

Current Sierra data, very different.

 

[DukeDuke]

Alliant's max for the 124s is 6,4gr of p pistol at 1157fps
I use 6.0gr in a 16" barrel at 1460fps, shoots great and soft

 

[TundraTim]

Hmm, interesting note about the Troy brass, I'll check that out for sure.

Thanks for the other feedback, much appreciated everyone.

 

[Mike Casselton]

From what I understand . Troy brass may use stepped brass . In order to use less powder. Be careful.
View attachment 1714929

I can swing over there either tomorrow or Tuesday and ask them about the brass.
I don't recall seeing a step in their brass when I picked up a handful out of their tumbler.

 

[TundraTim]

I can swing over there either tomorrow or Tuesday and ask them about the brass.
I don't recall seeing a step in their brass when I picked up a handful out of their t

From what I understand . Troy brass may use stepped brass . In order to use less powder. Be careful.
View attachment 1714929

I just checked mine and it is not stepped, maybe that's a particular caliber or an old product in the photo?

 

[TundraTim]

https://sierrabullets.com/load-data/ Chronograph velocity error?

Current Sierra data, very different.

I'm using a LabRadar, does anyone have any experience with those? I have not yet had the opportunity to compare it to another chronograph to verify it's accuracy.

 

[GLShooter]

I shot my LR side by side with a Garmin and a Millenium. I found the differences to be negligible within a foot either way

 

[neckturner]

I'm using a LabRadar, does anyone have any experience with those?

Yes, and they are fine.

 

[TundraTim]

I shot my LR side by side with a Garmin and a Millenium. I found the differences to be negligible within a foot either way

Yes, and they are fine.

Thanks guys, that's great to hear.

 

[RegionRat]

Also, when you look at pistol load data, try to consider the barrel length they used to publish their data.

There can be many reasons why a barrel doesn't match published data, but barrel length is pretty basic.

If the published data is from a 5" test barrel, and you are running a 3.41" barrel, you will not expect to match up.

If by chance you do, then the pressure is likely running high so be careful.

 

[TundraTim]

Also, when you look at pistol load data, try to consider the barrel length they used to publish their data.

There can be many reasons why a barrel doesn't match published data, but barrel length is pretty basic.

If the published data is from a 5" test barrel, and you are running a 3.41" barrel, you will not expect to match up.

If by chance you do, then the pressure is likely running high so be careful.

Thanks for that, unfortunately in this case the load data does not indicate what size barrel was used so it just adds to the mystery, haha.

 

[243winxb]

Lee data calls for minimum OCL of 1.150 and for whatever reason is used 1.130 by mistake

Internet said shorter COL (OCL) OR COAL will raise pressure? When pressure goes up, velocity is said to increase also?

Note that Sierra data uses a COL of 1.100" And less powder at 5.8 grs Power Pistol.
BE careful when going to a shorter COL. Maybe drop down to Sierras 5.8 Maximum?

Lee factory crimp die

A hard crimp may increase pressure, when it helps slow burn rate powder, burn better.

Primer used? Standard or magnum. May make a difference.

Checking velocity, as you make data adjustments, may tell us something?

Seating bullets deeper into the case will increase pressure & velocity. As will different brands of brass.

 

[RegionRat]

Thanks for that, unfortunately in this case the load data does not indicate what size barrel was used so it just adds to the mystery, haha.

Any time they don't list it, assume it is a 5" test bbl.

When you have time, look for multiple sources and similar loads just to get a feel for the variations.

 

[243winxb]

Power Pistol From 4.3 grains to 6.6 grains with 125 gr From https://stevespages.com/page8a.htm
Generic Reloading Data, much like Lee, that does NO testing of their own.

 

[TundraTim]

Internet said shorter COL (OCL) OR COAL will raise pressure? When pressure goes up, velocity is said to increase also?

Note that Sierra data uses a COL of 1.100" And less powder at 5.8 grs Power Pistol.
BE careful when going to a shorter COL. Maybe drop down to Sierras 5.8 Maximum?


A hard crimp may increase pressure, when it helps slow burn rate powder, burn better.

Primer used? Standard or magnum. May make a difference.

Checking velocity, as you make data adjustments, may tell us something?

Seating bullets deeper into the case will increase pressure & velocity. As will different brands of brass.

That would be an interesting test using the Sierra data to see how it compares. I'd need to check my notes but I believe I used Winchester WSP primers.

 

[TundraTim]

Power Pistol From 4.3 grains to 6.6 grains with 125 gr From https://stevespages.com/page8a.htm
Generic Reloading Data, much like Lee, that does NO testing of their own.

View attachment 1715118

That's a cool web page, I don't think I've ever seen it. I have been using LoadData.com, but I've only used the manufacturer data that they have.

 

[6MMsteve]

Barrel type the Glock barrel has a lot of resistance could be building, I have a barrel that is just standard rifling does that matter, I have a Lonewolf barrel and a couple I got off ebay I like the ebay barrels the best, lonewolf is picky...I really don't that much about barrels