before it was getting answers to problems with store bought bullets....now i'm using 180 grain BOOLITS that are powder coated.
personal note : i'am VERY meticulous when it comes to observances and measurements.
so here is what i know to be fact:
180 grain (wheel weight alloy) boolit....no lube grooves ...1 ogive with a flat meplat....beveled base and sized to 0.4015".
cases are used "win" cases sized, cleaned & re-primed with WSP primers, belled and chamfered.
all cases are 0.836" long on average. saami says max is 0.850 bu i have rarely ever seen a case that measures any longer than 0.840 ...i never trim them and don't anyone who does....saami also states a minimum O.A. L. of 1.085" to a max of 1.135" I tried 3 sizes of 1.120"---1.125"---1.130" with the same results.
my barrel IS throated and i'm positive that my crimp is minimal and the BOOLIT in no way makes any contact with the lands and grooves of the bore when in full battery.
when they do fire it is very accurate (dime size group of 3) off hand at 20 feet...(shot thru a chrony at just above 1000 FPS)
and it will fire the first 5 or 6 rounds perfectly.....however!after 6 rounds the chamber is so fouled that any rounds after that must have the slide physically pushed forward to fire it again ....and so on.
i'm using 7.0 grains AA#5 powder for 1000 to 1015 FPS
when it doesn't fire it is because the slide has NOT fully closed....about 1/8th inch.
so i measured the barrel and chamber .....here what i noted....
the diameter of the head space ledge = exactly 0.4243"
the diameter at the web = exactly 0.4273"
bore = 0.3895" on the lands and 0.4005" in the grooves.
so then i checked SAAMI specs.....and if i'm reading the schematic right, then this barrel is cut on the very minimum size that SAAMI states.
SAAMI also states in a box that i put a red square around this bit of info...."chamber unless otherwise noted all Dia. +0.004"
Does this mean that my chamber could be as much as 0.4283" at the case mouth?....and 0.4313 at the web? ....and still
be within SAAMI specs.? ...it also says "length tolerances +0.015".... which means it could chamber a 0.850 case properly....but that not the problem
again ...my problem is it gets too grungy in the chamber to push in another cartridge into full battery.
my thoughts were at first getting a stronger recoil spring ....but i dismissed that as it does nothing about the dirt.
then i remembered that "Glocks" are somewhat known to have a "more generous" sized chamber (i don't mean the un-supported part.)
i am of the idea that my chamber is just too tight and any grunge at all is just too much to make it cycle.
i've picture the SAAMI Spec. sheet below from their website.....and made a drawing of mine as well.
am i thinking right?....ream out the chamber couple thousandths? ......whats the worst that could happen?...buy a new barrel?