I have recently started shooting a 5.45 M&P15r. I was wondering if anyone else has any experience they’d like to share when it comes to optimal buffer/buffer spring combinations.
I’m planning on installing a Single Chamber Brake and ACT from ALG Defense, which I’ve already ordered. I also have already ordered a Blue and a White extra power buffer spring from Sprinco, and I just need to figure out which buffer to use. I plan on shooting those 1080 round cans of ammo from Aim surplus. I’m already am burning through my first can of the stuff, and the rifle has run well for it’s first 300 rounds.
If any of you have done any experimenting in these areas, I’d love to hear about it. I’m relatively new to the caliber, and I noticed that it seemed much snappier then the Sprinco Blue spring/H2 buffer set up in my 5.56 M&P15.
my 1st 5x45 came form smith. i had a red spring in it
put a h-2 buffer in it noting else
put a knac qd-4 connector on it
runs like a top
also have a factory 11.5" runs on same sbr lower
use asc mags and no worrie
do not use the c-prod new or old
use green spam cans runs great.
CLEAN IT WITH BALTiSOL (brownells) german stuff wierd. bubbles the corrosion right off
clean it when u get home at latest do not let it go a day or 2. bolt may be frozen. ask me how i kow that.
I was able to go out and shoot my M&P15r this last Saturday. I put exactly 60 more rounds through it with a couple of shooting buddies, and it went well. The ALG Defense Single Chamber Brake is superb, and though I was using irons the front sight seemed like it was staying on target with no effort. My other rifle has a red dot, so it isn’t an apples-to-apples sight picture comparison. The ALG Defense ACT trigger didn’t have any problems lighting off the surplus russian ammo, and the trigger seemed good for the price. Good being a felt improvement in the trigger pull while till functioning with surplus ammo.
My only issues came with the muzzle brake when I was cleaning the rifle. I had the upper under scalding hot running water to flush it out when I got home, and I noticed the brake was loose. So loose, in fact, I could return it to where it had been with my bare hands. I took it all the way off and went about cleaning the rifle, and messed with it some more after everything was ready to be put back together. I ended up using the original washer that had previously been holding on the A2 flash suppressor the rifle came with, and I used a healthy amount of blue loctite while I was at it. I’ll be keeping a REALLY close eye on it, I’m now kind of paranoid about it.
It’ll be fun to eventually get some kind of optic for the rifle and keep on running it.
I forgot to mention the spring and buffer set up I tinkered with. I started with the stock spring and carbine buffer. Nothing new there. Then I changed the buffer for an H2, and the bolt was still locking back. After that, I tried the H2 buffer with the blue spring from Sprinco, and that locked back, too. I may eventually add a red spring and an H3 buffer to the mix. I getting curious about how big a gas port S&W puts on their carbine length rifles…
I was able to hand tighten the brake until the top was a little past 9:00, if you were looking at the muzzle. I’d already covered the threads in blue loctite, and then I took a long wrench and tightened it until it reached 12:00. It took a bit of pressure. I’d liken it to bicep curling a 35 pound dumbbell, so hopefully it won’t move again. It wasn’t so hard I felt like I would damage the threads. The included washers from ALG didn’t want to index correctly. Together, they’d hand tighten to about 12:30, and if you split them individually(they can come apart into two but they come as one), one would hand tighten to 11:00 and the other to 1:00. The original washer was somewhat “belled” from the A2(though I don’t get how). By turning it backwards, it crushed flat and indexed right where I needed it to. Hopefully, it will be fine. If it loosens, I’ll see a gunsmith.
You can separate the peel washers easier by gently heating them with a torch and then just use as many as you need to get the brake to index to the 12 o’clock position. The individual washers are very thin. I didn’t have a torch handy in the shop so I used a razor blade to separate them into thinner and thinner individual washers. It took awhile. However, I did manage to get the brake to index tightly and correctly per the Geissele instructions. In retrospect I should have used a gas burner on the stove to separate the washers. It would have been a whole lot faster.
Blue loctite weakens and eventually vaporizes at high temperatures…like you would find on a barrel.
LewP-Thanks for the additional info. I thought I knew this, but the washer from ALG separated into two washers, and I thought that was as far as it went. It looks like I’ll be doing this process over again after I shoot the rifle again. Am I correct in understanding that the washers separate into more than two pieces?