90gr HDY XTP 9mm

[Hoons]

Loaded 5 cases with 6.6 gr Winchester Autocomp per HDY manual and chrono'd 1393 fps and 27.43 std. Dev.

Wanted to ask the experienced folks do you see any pressure signs on the primers? I'm still relatively new and don't have a feel for high pressure signs.

 

[outrider58]

Don't have my Hornady book in front of me, but velocity seems high. Load seems over advertised max too, but different bullet.

 

[outrider58]

There seems to be flow, but super closeups are often scary looking.

 

[Hoons]

What is flow?

 

[Hoons]

I used Hornady's load data. They specified 6.8gr as max load to achieve 1400 fps.

 

[BUFF7MM]

What is flow?

The movement of the metal in basic terms.

Understanding Pressure :: Primal Rights, Inc

Reading pressure is a required skill that all shooters must have. Whether you are shooting factory ammunition or your own handloads, you absolutely must be able to detect and interpret pressure signs on your fired brass.

www.primalrights.com

 

[Sticky]

What was the overall length of the finished cartridge? I'll run the numbers through some programs to see if I can get you some pressure data estimates... This is the 35500 90gr xtp, yes?

 

[Hoons]

What was the overall length of the finished cartridge? I'll run the numbers through some programs to see if I can get you some pressure data estimates... This is the 35500 90gr xtp, yes?

1.07" oal

 

[Hoons]

And yes it's the 35500 90gr xtp

 

[Biggfoot44]

Case head expansion is better for judging pressure than primer visuals .

 

[Sticky]

GRT says you are still within spec with those numbers...

 

[Sticky]

It also predicts your velocities should have been around 1400fps, so I'd say it's pretty spot on.

Edit to add, that was based on a 5" bbl length. I can adjust that if you want, but it will just drop the velocity a bit.

 

[Hoons]

Very cool tool! I'm going to have to look into one of those. I was using a threaded glock 19 barrel with 4.5" length. I'm surprised I was able to achieve that velocity with the shorter barrel.

 

[Park ranger]

I think your ok.

 

[Biggfoot44]

Very cool tool! I'm going to have to look into one of those. I was using a threaded glock 19 barrel with 4.5" length. I'm surprised I was able to achieve that velocity with the shorter barrel.

One of the advertising claims of Glock , is their Polygonal rifling giving higher velocities than otherwise identical conventional bbls .

 

[Hoons]

One of the advertising claims of Glock , is their Polygonal rifling giving higher velocities than otherwise identical conventional bbls .

This was silencerco threaded barrel, I think they have conventional rifling.

 

[Biggfoot44]

So much for that one !

Perhaps it has a minimum spec chamber .

 

[atblis]

That’s from a Glock? Pretty odd looking primer swipe IMO. That almost looks like a timing issue trying to unlock while still under some pressure. Autocomp is noted as being extra gassy so perhaps that’s not indicative of an issue, just the nature of the beast.

If your inside the published load, and hitting the expected velocity, I wouldn’t worry too much.

I’ve done naughty things with Longshot in various Glocks and never had a primer end up looking like that.

 

[Hoons]

I'll see if I can load some and fire in my m&p to see if I get the same primer swipe

 

[alucard0822]

That’s from a Glock? Pretty odd looking primer swipe IMO. That almost looks like a timing issue trying to unlock while still under some pressure. Autocomp is noted as being extra gassy so perhaps that’s not indicative of an issue, just the nature of the beast.

If your inside the published load, and hitting the expected velocity, I wouldn’t worry too much.

I’ve done naughty things with Longshot in various Glocks and never had a primer end up looking like that.

was thinking the same thing, looks like an M&P primer mark, not GLOCKs usual square-ish imprint. Even so wouldn't worry much, but would measure the case head expansion to be sure. You can do some fun things with 380 bullets in 9mm and other cases. 9x19 is a really strong case and forgiving, so you can push it harder than some others. I use those 90gr XTPs in 9mm and get about the same 1400 FPS-ish in a full size 9x19 pistol, or 1600+ in my 38 super