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Old 08-29-2004, 20:06   #6
militarymoron
Guerrilla
 
Join Date: Jan 2004
Location: email: militarymorons@gmail.com
Posts: 153
sorry to resurrect this old thread, but i got a chance to do a bit of informal testing with the polymer cased PCA ammo over the weekend. i had two different loads with me - the commercial 55 gr FMJ load with grey cases (lot # PCA04 jul B) and the new "military load" 62 grain (lot # PCA M855 0604) with white cases. the neck tension in the commercial load was a concern - the bullet could easily be removed just by pushing it over with the thumb. when pressed against a hard surface, the bullet would be pushed back into the case. however, with the military load, the neck tension is a lot stronger, and i'm unable to push the bullet into the case or remove it by hand. PCA addressed the neck issue on the military case.

here's a summary of our shooting session:
rifle A - LMT MRP upper receiver with 14.5", 1x7" twist barrel. Colt bolt carrer, LMT enhanced M4 bolt.
rifle B - bushmaster upper receiver with 11.5", 1x9" twist heavy barrel, bushmaster bolt and carrier, Troy Industries MRF-C rail forend.
rifle C - Stag arms upper receiver with 11.5", 1x9" heavy barrel, ARMS SIR forend

lowers were all bushmaster select-fire registered receivers.

magazines used were 30 rnd USGI and 30 rnd thermold.

ambient temperature at time of testing was approx 92° F and humidity was 45%

1. rifle A - commercial load, 20 rnds semi - no malfunctions. 20 rnds FA, 2-3 round bursts - no malfs.

2. rifle B - commercial load, 28 rnds FA, short bursts - no malfs. 28 rnds FA, long bursts, no malfs.

3. rifle C - military load, 28 rnds FA, long bursts - no malfs.

4. rifle B - military load, 80 rounds in 4 magazines, short and long FA bursts, no malfs.

5. rifle A - military load, 50 rounds in 2 mags, long bursts, no malfs.
50 rounds in USGI mags, short bursts, semi and double taps - no malfs.
50 rounds in 2 thermold mags, both unloaded in 25 round continuous bursts, no malfs. a round was loaded in the hot chamber and allowed to sit for about 5 minutes immediately after, and when examined, no melting or effect on the case was observed.

i had soaked 20 rounds each of the military and commercial ammo in a container of water for about 48 hours. all rounds were completely submerged. water was drained at the range and the ammo loaded and fired immediately.

commercial load in rifle A - no malfs.
military load in rifle A - 1 failure to fire. primer had normal strike on it.
i fired the remaining ammo out of rifle A and B using a combination of mags, on the move, on both semi and full auto, with no more malfunctions. my inital concern with being able to remove the bullet in the commercial load with thumb pressure is still a concern.
some of the commerical cases suffered partial seperation at the neck, while the military cases showed no sign of it. i'd feel a lot better about using the commercial load if the cases held up like the military load.

summary: 120 rounds commercial - no malfunctions.
400 rounds military load - one malfunction (soaked round, failure to ignite primer).
it seems that with the military load, PCA might have worked out some of the bugs that the commercial loads were experiencing.

cheers,
MM
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