10mm field pistol -- FN and G5 20

[GJM]

In the past, after much trial and error, I gave up on a 10mm field pistol that would feed heavy field loads reliably. On account of its reliability, the USP FS with .45 Super loads was what I settled on. As I became an almost full time optics shooter, I recently moved to the Glock 23 MOS and ultimately a G19 with an Acro and Underwood penetrator ammo for field use.

I am aware that Clusterfrack got a Glock 20 running reliably for him with hand loads and some equipment mods to the pistol. With the release of the Gen 5 Glock 20 MOS and the FN 510, I decided to try both pistols with heavy field loads and see if they run reliably in more or less stock form. I ordered in 250 rounds of Underwood coated hard cast and their load with the Lehigh penetrator bullet.

Assuming both pistols arrive at the LGS, I hope to begin testing soon.

[1slow]

I very much appreciated your work with HK USP 45. I really enjoy my LEM/ Match hybrid USP 45s.

I am glad you are researching the field auto again.

[CCT125US]

If proven reliable, what pros and cons do you expect to see from the 10mm UCHC and LP, over the G19/Acro/UEP? What results would make you pick one over the other?

[cheby]

Any reports on Sig320 10mm, BTW?

[El Cid]

What about using the Extreme Penetrators in 10mm? Is a hard cast bullet going to be that much better? My G40 runs like a sewing machine with the Underwoods. It does the same with the Federal Trophy Bonded - though I have no idea how effective it is on 4 legged critters.

[cheby]

What about using the Extreme Penetrators in 10mm? Is a hard cast bullet going to be that much better? My G40 runs like a sewing machine with the Underwoods. It does the same with the Federal Trophy Bonded - though I have no idea how effective it is on 4 legged critters.

My Glock 20.4 didn’t run with both of those cartridges

[rjohnson4405]

Was hoping to see you try the new M&P too!

I had an HK 45C loaded with supers based on your recommendation and my own testing but I could see myself moving wholesale to the m&p platform if it worked.

[GJM]

Between general 320 concerns, the complexity of the FCU is field conditions, and some reports that the 320 didn't function reliably with heavy field loads, I didn't consider it. I saw similar function issues with the M&P, and I am not keen on the M&P optics mounting system, especially with heavy loads.

In terms of the benefit of a 10mm over 9, it really is just diameter and mass. I have never been around a dangerous animal and thought I would rather have a smaller caliber. However, reliability trumps everything else for me in a field pistol, and it will take some testing to assess function with 10mm loads. Lehigh Xtreme penetrators are one of the two loads I purchased.

[Tarrrnation!]

Thanks for your work. I just put a layaway on a Gen 5 Glock 20. Since my state is a complete mess currently gun-purchase-wise (The clusterfrack that is Oregon) it will likely be months before I get my hands on it. I look forward to your findings.

[GJM]

The Gen 5 20 MOS arrived today. Trigger felt very Gen 5 dot rolly good, which should work well on a field pistol. I disassembled the pistol, lubed in the right places and confirmed the striker channel was clean and dry.

I installed CHPWS low height BUIS sights. The front sight flipped around either side of plum, and I had to do some Kentucky windage with my thumb to get it reasonably straight as I tightened the front sight retaining screw. Rear sight took some hammering as my standard Glock rear sight tool wouldn't work with the larger G20 slide. Putting a few coats of white and then orange paint on the front sight.

Used a CHPWS EPS MOS plate to mount a six moa red EPS full size. The Wheeler laser says the EPS and plate was within an inch or so at 25 yards as everything came out of the package. I figured 10mm will be a good test of the optic and plate. My backup plan is a TD plate and an Acro, and if this pistol makes it to field use, that is likely what it will end up dotted with.

Will let it cure overnight and then do initial shooting with 100 rounds of S&B before going to the Underwood.