cking

So bored today in between watching a slow moving storm and intermittent rain, what to do? The Loctite is dry let's test the 692 with TK custom moon clips, red dot and grips before range trip to zero. So I load up a TK CLIP with the aluminum cased federal 115gr 9mm ammo. Open the porch door and put 7 shots in the dirt, come back in to inspect primer strikes. Gun and sight functioned well, but I open the cylinder and push the ejector rod and it says no. I push harder, still no, so I take cylinder out, just a button push. Look thinks over and tap the ejector on the desk and finally they eject. I inspect the cylinders and they look fine just that nitride finish. Now I want to use Alum case ammo but sure won't be any fast reloads. So I get cylinder polishing hone brush out and the oil it needs and I slick up the cylinders. I had already bevel the edge, but now fresh moon just falls right in. Test again still STUCK, so I lube the cylinder with a little spray silicone, test, better but no prize. Test with brass, fly's right out. Now I know why my 1911 plate gun eject the alum cases about 1/2 the distance of the brass cases. So can't use alum case if you might need a fast reload.

Hurricane screwed up range day, TC VS Taurus moon's. Weigand mini mount,

Got my Thailand grips in had to remove lots of wood but they don't rattle.

He only used the channel locks for the last round, and he had bandage on finger

Things are going well, the Wolff spring pak from Brownells came in and I installed the 10 pound trigger and hammer springs. Did a little polishing inside the frame, installed some Powers washers for trigger and hammer to keep them centered, cut 2 coils of the hammer and 3 off the trigger. Recut the trigger face to improve the SA pull it creeped. Mainly want a light smooth DA pull. Beveled slightly the edges of the cylinder. Also cut 2 turns off the cylinder catch spring, it is the same as the 1911 mag catch spring, the tension made the cylinder open slowly. Found a guy on ebay that makes old style S&W square butt grips for $50 from eBay, plan to remove excess wood till the fit my hand. Weigand makes a short rail that uses the rear sight screw for the Vortex Venom 6 moa dot. TK custom makes moon clips. After shooting I won't be lightening the barrel under lug, limited testing with federal 115gr convinced me leave it alone. Also the MIM parts polish very nicely and I was able to get mirror polish on the trigger, this is steel gun. The Mim parts in the S&W stainless guns also look like packed sand under 12x magnifier. When grips and dot are on I shoot from a bag at 25yds with federals give you 7 shot groups size. So for gun $491 , Grip $50, Base $40, Venom $206 total $787.00 or the starting price of S&W.

I found a Wolff spring kit with reduce rates, stock is 14# kit comes 10,11,12, and two reduced trigger springs. The biggest hassle is nobody make a wood grip. The factory grip is terrible, leaves my pinky with nothing to hang on too. I'm not a lover of Rubber grips and monogrip frame allows lots of freedom, but I guess is too new. I will test for accuracy after the springs go in.

Just got today and for just less than $500, I'm impressed. Tore it apart and did a typical DA job, no spring trimming till I get more. MIM parts but are nice and hard and stone well gave good finish. To heavy barrel but I can mill off the under lug. Don't like grips, short and rounded like a carry gun. Cylinder fit and timing better than any S&W Star was hand cut bye somebody with skill, both cylinders perfect. So summary buy it and spend the money you didn't spend on the S&W for typical trigger job and be happy.

Tru dat

From the problems of ejection, bolt speed is important, from the brochure if your ejections are in the 1 to 3pm range you are on the edge of a problem, the empty has not been released from the extractor and or cleared the bolt before bolt starts moving forward again and is kicking the empties forward. With the 2 oz weight my empties are coming out at the 4 to 5 Pm range and from the film I had taken half the empties are hitting me on the right shoulder or going over it, I'm left handed, also why I like my bolt to stay locked longer, so the gun doesn't spit in my face. Which all blowbacks do and even some MPX's spit on you till they get the updated bolts. Also holding the lock longer really softens the impulse as more energy is burned opening the bolt against a heavier lock. A soft shooting gun allows lower split times especially on a steel plate rack. Never loosing focus on the next plate and being able to see the plates fall and noticing a miss plate sooner just makes you faster. My goal is to be almost as fast as those shooting 22LR.

What this shows is that even though it is a locked bolt with a radial delay it is still a recoil operated gun so the mass of the bolt, carrier, buffer spring all matter. More like a 1911 or H&K roller lock. Which pretty much means that case blowout if far less likely. So Alum cases don't cause a risk increase.

This isn't a blowback gun

CMMG has replaced some bolt and carriers for failure to eject and bolt over base jams. My new bolt exhibit excessive recoil impulse when compared to the original bolt, similar to a regular blowback. See pics. I believe they changed the bolt locking lug angle and possible the cam slot in the carrier. Even with a 308 flat wire recoil spring and HYD buffer bolt speeds were too high. All development using federal 9mm 115gr Alum rounds. So I ordered the tuning kit. I installed the 2.0 oz carrier weight and now things are back to normal. The increased carrier weight slows down the unlocking because of increased inertia, no amount of recoil spring weight changed the carrier velocity. Read the instructions sheets for more details of tuning. Happy again and with a very soft shooting

magpul moe k2 + this is more vertical grip handy for short stocks and flat triggers

CMMG responded the weights are standard in blow back gun not in the guard, got no response on the change in felt recoil, I'm still going buy a set and see what effect they have.

If you go CMMG https://www.cmmginc.com/product/action-tuning-kit-mkg/# it's says 3.4 oz standard for 9mm DOES anybody carrier come with the weight?

Shot mine today at a steel match, not happy way to much recoil, going to try adding carrier weights.

I've wondered why some many different opinions on felt recoil of the Guard. My first bolt was extremely soft shooting but failed after some 1500 rounds. The new bolt is far from soft and works well with a flat wire 308 and hyd buffer but it slings the brass. I found some close shots of the first bolt will have take some pics of the new version and see if we can any difference. Been busy rebuilding my surface pro 4 MSFT gave me a new one due to screen flicker heat problem.

Update of new BCG. CMMG put a new BCG in my Guard, it runs! However the recoil impulse is noticeable harsher even with 223 flatwire and hyd buffer. Which makes me think they changed the angle of the locking lugs to leave more momentum in the BCG. So now I'll move on to testing a 308 spring and probably a 308 flat wire.

Here is the thread and patent link https://www.ar15.com/forums/AR-15/CMMG-GUARD-ROTARY-BOLT-QUESTION/15-731462/

I like the simple one CMMG sells for less than $50. https://mantisx.com/pages/how-it-works-1 Take look at this product, I've talked with them about using it to compare comps, they say they are working on it. If the collection speed is fast enough this thing could help you tune your gun, bullet weight, charge, springs, buffers, even LOP, COMPS.

I think it more about your stance, if you using the squared approach then the trend is shorter LOP. I like short LOP and light/short barrel for fast close work. I like my charge handle close my nose, I feel it helps me move the gun faster. What I haven't worked on is the notion of move the head and gun will follow is faster than drive the gun to next target.

In hopes of saving this project I ordered a new bolt. What I'm thinking is too much play when bolt is locked, will measure the new next to the old. I found using a weaker spring cured the bolt over run jam

Since the angled locking lugs of the rotary delay never really lock and show signs of battering I.e. setback will you end up with excessive headspace. If so would a symptom of excessive headspace be failure of the extractor to fully seat in the rim groove? Which would show as a failure to eject, not extract. As the case is blown out because it is somewhat of a blowback design. I have trouble with and extracted case being shoved forward by the ejector but not rotating out on the extractor. Or is this all hogwash, because on bolt closing the barrel extension and bolt face slam into each other allowing the extractor time to hook the round. So excessive headspace would be function of chamber depth. So case length becomes critical. Also extractor groove size compared to rim thickness are there any recommended standards?

SUCCESS BUT NOT WITH MOD 2! Now runs with Federal 115gr ALUM Actually mod 2 was the worst FTE's every other round, but I learned something … I was wrong on less extractor needed, just the opposite more is needed. So mod 3 is mod2 polished extractor with a brownell CS spring with black insert and CS ejector spring and polished the walls of the bolt. I think the bolt face was hair too small. So take the bolt apart and take fine cratex on your Dremel and polish the bolt recess and edge and smooth the extractor put brownell CS springs in. Now I can go back to the flat wire and hyd buffer too see if things are back to normal and I can run Cheap alum ammo Now I get back to drilling the lower for lefty mag release going right in front of trigger about the size and shape of 1911 mag release. The reason is for the man on man match we shoot you are required to make change before you shoot the dueling popper. Just two slow too use my right hand to release the mag and then put new in. With new left side release the trigger finger will release the mag while right hand is bringing a new one up. Should save a solid half second.

Tthinking about CMMG and it always extracts but some times doesn't eject. I had bolt out and was examining again the bolt and the round interaction. Found there was still spot were the round would hang binding between the extractor hook and the recessed bolt walls. Inspecting ejected cases showed that ends of extractor hook had scored the rim. So the pistols and some PCC bolts use a extractor like on the 1911. So I narrowed the extractor, but still some binding, then I polished the bolt walls. That made the difference there is NO position that case will hang, it always falls. So I waste some more ammo testing.