MickB

Adjustable gas blocks can be finicky things. Don't clean the gun for another couple hundred rounds and verify that the bolt still locks back. With regards to temperature, on my JP15 I had the gas adjusted perfect for 95 degrees. next day, temp dropped to the mid 50's. Rifle wouldn't cycle and eject at that temp. My suggestion would be to either try the rifle when the ambient temp is lower, or find your nearest indoor range and ask what their AC is set at. Hopefully you find someone who sets theirs at 65 degrees... :-) Mick

I have used the SLR SA7 adjustable gas block with the original DPMS gas tube. Initially I tried the set screw version, but sent it back as the rifle would not lock back on an empty mag - I thought the block was leaking gas. SLR replaced it with a clamp on version. Only later did I find the problem was the Magpul Gen 3 mags! The rifle functions fine on a setting of 5 on the gas block. With the DR brake, the recoil is straight back, with zero muzzle rise. I also had the MI SSK rifle length handguard, but found it too skinny for my hands. Super lightweight at 9 oz and cool HG, though. Took it off to replace with the Samson Evo, of which I have a couple on other AR's. The Gen 3 mags can be made to work if you round the edge of the follower that sits under the right mag feed lip. Taking a little bit of material off that corner allows the bolt catch actuation tab to come up higher (needs 0.03-0.05"). I've been talking with Justin Beard and Rob Ritter at Magpul, but responses have been slow. Mick Yep. I agree completely regarding the feel of the GII compared to the other 308 AR's I've owned/shot. What are you using for a gas block? Are you using the factory DPMS gas tube or something else? Also, do you have a point of contact at Magpul? I wouldn't mind calling to express my concern over the lack of hold open with the new mags. Sent from my Torque using Tapatalk

Like the title says, has anyone tried the TTI light buffer spring in their AR? Says it works in both rifle and carbine buffer tubes. It is supposed to be used in rifles with adjustable gas and light carriers. Wondering if anybody has tried one of these and noticed a difference, like being able to turn the gas down further. Mick

I used the tail of my caliper to get a depth measurement and I will admit to eyeballing where the hole started, so it is possible the gas hole began at 0.235" on mine as well. However, there is no way it was 0.295". Mick Either your caliper is off or you measured incorrectly. I measured .236" and Todd Gardner, owner of SLR, confirmed it was .235", or .295" from the center of the port which is .12" wide Edit: He did mention having 3 production runs of the SA7 block. Maybe he changed to milspec (.295") along the way. Dunno.

I just wish you could get the frame mounted safety versions here in the US.... Mick

Adding an adjustable gas block and DR brake did wonders for my G2 Recon. Those changes really tame the rifle. holding a gen 1 and gen 2 side by side, the gen 1 feels like a brick. The gen 2 feels like holding a regular AR15. Night and day difference in feel.... Mick

The gas block adjustment instructions should be on a separate sheet that is with your accessory pack. There should also be the test target showing group size at 100 yards that specifies the type of ammunition used. Colt Competition guarantees groups of 1" or less at 100 yards. What does your test target show? Try the same or similar ammunition to what the rifle was tested with, and has already been suggested, try to remove yourself from the equation. If the rifle still won't group, call Colt Competition and use the Warranty... Mick

Just measured my SLR Sentry SA7. Gas port begins 0.215" from the edge of the gas block.... Mick

Each Colt Competition Rifle is test fired at the factory, and there should be a card with the rifle that shows the group fired. I would suggest you tune the gas system per the included instructions... Mick

I tested an Urbino stock on my VM Tactical and found it a little short, also. Worse was that I found that it induced failure to feed malfunctions. I could go back and forth between the Urbino and the factory stock and the malfs followed the Urbino. The only thing I can think of is that my particular Urbino sample put excessive pressure on the recoil spring tube... Mick

They are the same... Mick

Looks like the Toolcraft Ti carrier is 1 oz lighter than a JP steel LMOS, and 1 oz heavier than the Boomfab. Mick

Set screw gas block only pull down in the area around the gas port. Should the screw(s) ever come loose, there goes your gas seal and problems can result. A properly mad clamp on gas block should be tight to put on, and should need to have the bottom opened with a flat bladed screw driver to get the gas block on over the gas pad on the barrel. When tightening the screws, a clamp on will pull the block down over the gas port, as well as seal around the sides of the barrel - you can't get that in a set screw gas block. That is not to say that set screw blocks don't work - they do. I like the way Noveske does them, a set screw with a taper pin through the block and barrel. Mick

Aimpoint PRO is best bang for buck by far. comes with mount, 2 MOA dot and can be had for $360-400. Mick

Any clamp on gas block will hold better and seal better than the set screw type... Mick

I'm with Patrick. Forks down and no issues changing gear.... Mick

The firing pin retainer in the bolt carrier is held in place with a rubber O-ring, which sits in a groove in the carrier. Your o-ring may be missing, or broken. Strip the gun, pull the retaining pin and verify. Remington will send you a new one if it is missing or broken. Try swapping trigger groups with the Sportsman and see if the trigger group is out of spec, or the receiver. Mick

Word direct from Dillon was to remove the expander ball completely for max neck tension.... Mick

Chris, in your testing, did you ever test the JP LMOS carrier with a gutted carbine buffer or TACCOM buffer? The recoiling mass between the two systems should be the same. However, performance could still be different due to the different mass distribution. Lightest setup of all would be the Boomfab carrier with gutted carbine buffer or TACCOM buffer. I would be interested in the results of the above tests. Mick

Is there any recoil difference versus the standard JP recoil spring and 3oz buffer setup? Mick

So, Ti BCG + carbine buffer = JP LMOS + TACCOM buffer. Can these be run with a TACCOM buffer or gutted carbine buffer? Mick

Then go with your number 2 choice.... Mick

Yes, I have been. I need to prod them again on this issue... Mick

So I am playing around with a .308 DPMS G2 for possible entry into the Heavy Metal Division. With the current modifications, I have the rifle shooting dead flat. Rifle in question began life as a DPMS G2 Recon, to which was added an SLR SA-7 adjustable gas block, Midwest Industries SS2 KM rifle length handguard, Dynamic Resistance muzzle brake, Hiperfire 3G trigger, and Magpul STR stock on a mil-spec carbine buffer tube. Right now I am shooting military surplus 147gr FMJ at ~2,850 fps. As I mentioned earlier, the rifle is shooting dead flat, but there is a definite rearward recoil impulse that makes getting the followup shot on a target not as fast as with a .223 AR pattern rifle. My question to the Heavy Metal gurus is am I using the right ammo? Should I be using heavier bullet weight at lower velocity to reduce the rearward recoil impulse? Am I just fighting the basic laws of physics expecting the .308 to feel like a .223? Do I just need to hold the rifle like a real man and suck it up? I am trying to get a point of reference between the .308 and .223 rifles used in our game. Mick

Update, myself and Kampr tested the Voodo ULW barrel upper at the end of today's 3 Gun match. With the standard 3 oz carbine buffer, there was some noticable muzzle dip. Moving to the TACCOM ULW buffer system, the muzzle dip was a little less. This rifle barely weighs 6 lbs and has a JP muzzle brake on the end of the barrel. So, it would appear that the lower reciprocating mass is having an impact when the bolt closes. So, I am wondering if next steps are to change the recoil spring, or try tuning/changing the brake. The recoil spring in this particular lower may be some "enhanced" version that came in a kit. I will change out the spring and check the effect.... Mick