need advice

[jonny rotton]

i had an ar stoner 18" barrel cut down to 12". it is a mid length gas system.
do i need to change the gas port? should i use a fixed or adjustable gas block??
i shoot hornady sst factory ammo and wolf steel case.
any advice is welcome and appreciated.
jr

[diddlyv]

In theory the case will have a net lower pressure as the bullet will exit barrel 6 inches quicker. If the rifle functions without doing anything you are GTG, if it no longer ejects and locks back when a single bullet is loaded in a mag you will need more gas hence an adjustable gas block but without testing don't think there is a good answer

[Rickc]

You have built a short barreled rifle.

I hope you know what that means

[LRRPF52]

All of those that I saw already had a .0935" gas port, so I would shoot it and see what happens.

[keystone183]

Very interested in doing something similar!! Please let us know your results! I'm with lrrpf though, if that is the dia of port...should be good to go. Going to run suppressed i'm guessing? I'd use an adjustable block either way.

[jonny rotton]

i have ordered both fixed and adjustable. they should be here soon. i will try one and see what happens. i am fairly new at the Grendel, this is my fourth build. i do absolutely
love the cartridge and what i can do with it. i will post results once i test it. thanks for the advice.
jr

[LRRPF52]

I would install the adjustable block and follow their instructions on how to dial-in the gas.

[jonny rotton]

I would install the adjustable block and follow their instructions on how to dial-in the gas.

i was thinking of using the fixed because i thought that under gassing would possibly the problem not over gassing. your thoughts????

[LRRPF52]

i was thinking of using the fixed because i thought that under gassing would possibly the problem not over gassing. your thoughts????

Only one way to find out. You're in uncharted territory to the best of my knowledge. I haven't seen many MLGS barrels shorter than 16" in this cartridge.

[jonny rotton]

would a fixed gas block and an adjustable wide open be the same?? or would the adjustable be able to let in more gas than the fixed??
anyway i can't wait to get it running as a PISTOL.

[Drillboss]

A fixed gas block should be letting through all the gas that is available from the port. An adjustable block can't do anything but restrict that gas flow.

You would need to drill out the gas port if your system is under gassed.

[jonny rotton]

okay, i put on a fixed gas block with the mid length gas tube. one shot with steel cased wolf. it locked back on the empty mag. HOOORAAAH
now how can i tell if its over gassed?????
thank you all for your ideas and opinions.

[jonny rotton]

the empty brass of wolf steel hit the ground about 10' from where is was shooting offhand and slightly to the rear from a 90 degree angle. is that good????

[VASCAR2]

the empty brass of wolf steel hit the ground about 10' from where is was shooting offhand and slightly to the rear from a 90 degree angle. is that good????

Sounds good to me, if there is to much gas the brass usally is kicked out at 1-2 o'clock. Wolf steel case is not very hot ammo and you'll see a difference in ejection pattern with factory Hornady. My Carbine gas 16" 6.5 Grendel kicks factory 123 grain A-Max out to 1-2 o'clock and Wolf goes out at about 3 o'clock. My carbine upper has plenty of gas.

[jonny rotton]

thanks vascar2 for the infor. it kicked it out about 3:30. looks like i am good to go!!!! i am taking my 16" into the mountains of montana to look for elk. my license and tags for both elk and deer was a staggering $36. to make it even better we got some snow last night.