Problems with failures to feed with Underwood Ammo, Gen 4 Glock 20

[The_Shadow]

Yes Hickok45 did have a misfed in one of his Glock 20 and glock 29 videos...using some cast WFNGC from one of the makers, while it was the only one it did raise some concerns.  One of the main causes can be the angle of the cartridge as it tries to enter the chamber, these wide flat noses can drag the feed ramp and the upper reaches of the chamber if seated too long.  If I recall, DT was seating his stuff to 1.242" to help feeding issues by allowing more tipping angle.

High Impulse rounds can increase slide velocities to the point of over running the feeding from the magazine.
Some have noted that recoil systems using round wire springs in the Glock 20's, were found to bunch up, adding drag or short stroking of the slide.

There is a delicate balance for things to work in unison! 

[pacapcop]

Hickok45 was using Buffalo Bore 220 Lead with a stock barrel.

[DAVIDF]

Semper Fi,

My 20 was supposed to replace a Super Blackhawk, but no big bears that like to eat you here. Only mild mannered black bears that run the other direction. Hopefully the new gun will work with heavy loads, but I don't need it to work with the heaviest cast loads. I was thinking of trying Wolff magazine springs, but when I described my problem to them, they didn't seem to think that would help.

Ezveedub,

I measure OAL on a few of the Armscor 180gr vs Bazer & Underwood 200gr XTP. The Armscor is maybe a couple thousands longer than the Blazer at about 1.251 and the Underwood was longest at about 1.255. The Underwood 180 gr TMJ was shorter at about 1.245 (if I remember correctly) & it fed better than the Armscor. I'll keep better notes with this new gun while I'm seeing what works & what doesn't.