Kel-Tec Sub 2000 FTE's with A&E 147gr

[BIG45-70]

I've now run around 300 rnds of American eagle 147gr through my Glock 17 version Sub 2000. In this much of ammo I've had about 5 FTE's, usually on the last round sometimes not. I'm using factory gen 3 glock 17 mags. It runs fine with 124gr Sellier & Bellot. Anyone have an idea what the problem is?



This is the ammo I was using. No feeding problems of any kind. Just ejection. It should be noted all of the brass casing had a small dent on the case mouth, every case I could find have the same dent.

 

[bigfatdave]

sounds like the timing is off a bit with that pressure and the resulting blowback speed ... you could swap springs or just not use that exact ammo.

 

[BIG45-70]

(newbie) How does the ammo make a difference in the timing of the bolt? How big of a difference in pressure change would there be by changing to something like 124gr or 115gr ball ammo? How would this change the timing of the bolt?

 

[Owen]

Fail to Eject, or Fail to Extract?

The ammo affects the bolt speed tremendously in a blow back gun.

After firing, the momentum of the bolt is approximately equal to the momentum of the bullet.

momentum is mass x velocity.

 

[BIG45-70]

All the casings extract from the chamber fine they just don't kick out the ejection port and end up getting crushed between the bolt and chamber. Sometimes I've run through 100 rounds without a problem and others ill have one failure per box.

 

[rcmodel]

Well, my WAG is, they are not as powerful as the other S&B ammo that works.

S&B is loaded to full European CIP pressure, which is the same or slightly higher then American SAAMI max pressure.
American Eagle is econemy priced plinking & practice ammo, and is not loaded very hot at all.

As a result, bolt speed is low, and they are not hitting the ejector hard or fast enough to knock them out of the gun.

rc

 

[Owen]

what RC Model said.