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Stuff like this?
Yup. I have the a FCD BCG like in that video also.
Stuff like this?
I assembled my first upper receiver from parts. I got an 18" 223 Wylde barrel from Green Mountain, and fixed it to a vacant upper receiver. I put some blue loctite on the gas block screws. Put a little bit of hi-temp grease on the barrel threads, lined everything up. Admittedly I didn't torque it, but I do enough wrenching on my cars to know what 80 ft-lbs feels like. Backed it off to "season" the threads, and cinched down again. New BCG from PSA. Put a little lube on the sliding metal to metal contact points. Am I missing anything?
I'm nervous as hell thinking about shooting it though. It seems to go into battery fully. Anyone else been in this situation and how did you double check your work? I'm thinking about "remote firing" it a couple of times so I don't kill myself.
Did you watch videos online to assemble it? I'd quickly watch a few and just make sure you.did everything correct.
Imo lube up the entire bcg and inside the upper. You can always clean excess but over lubing isn't really a thing unless you seriously go full retard. There is however such a thing as under lubed. I've quickly wiped bcgs and uppers then coated them in rem oil, clp, or whatever to the point they are dripping while reassembling them. It's not a problem, might be a bit messy. They certainly don't need to be dripping and I don't usually use that much but I like everything decently coated.
You can buy go & no go guages and check headspace if you want. Pretty easy to do.
Depending on your planned firing schedule, once you confirm it functions remove the gas block set screws and clean the blue loctite off of them. Gas blocks get too hot for blue. Some people use red but depending on your firing schedule that might be insufficient. I prefer rocksett, similar breaking strength as blue but holds up to heat. If you ever have trouble removing water breaks it down. Up to you, if you aren't going to be getting it that hot it might not be a big deal.
Thanks. Yes, I watched a few videos. I was wondering about blue loctite being sufficient, and was worried the block might fly off under the stress.
This will be a target-shooting , light-duty upper; California Legal. I have different SHTF equipment for when the next earthquake/tsunami hits, or BLM comes to town.
I assembled my first upper receiver from parts. I got an 18" 223 Wylde barrel from Green Mountain, and fixed it to a vacant upper receiver. I put some blue loctite on the gas block screws. Put a little bit of hi-temp grease on the barrel threads, lined everything up. Admittedly I didn't torque it, but I do enough wrenching on my cars to know what 80 ft-lbs feels like. Backed it off to "season" the threads, and cinched down again. New BCG from PSA. Put a little lube on the sliding metal to metal contact points. Am I missing anything?
I'm nervous as hell thinking about shooting it though. It seems to go into battery fully. Anyone else been in this situation and how did you double check your work? I'm thinking about "remote firing" it a couple of times so I don't kill myself.
I assembled my first upper receiver from parts. I got an 18" 223 Wylde barrel from Green Mountain, and fixed it to a vacant upper receiver. I put some blue loctite on the gas block screws. Put a little bit of hi-temp grease on the barrel threads, lined everything up. Admittedly I didn't torque it, but I do enough wrenching on my cars to know what 80 ft-lbs feels like. Backed it off to "season" the threads, and cinched down again. New BCG from PSA. Put a little lube on the sliding metal to metal contact points. Am I missing anything?
I'm nervous as hell thinking about shooting it though. It seems to go into battery fully. Anyone else been in this situation and how did you double check your work? I'm thinking about "remote firing" it a couple of times so I don't kill myself.
All good points, thank you. @RerouteToRemain Do the knurled set screws eliminate the need to dimple the barrel?
How was the gas block fitment on the barrel?
If it was a tight fit, the knurled screws properly torqued with red loctite or rocksett without dimpling and your firing schedule you will more than likely be good to go.
I'm going to disassemble it and double check everything. I might check into using Rockstet after seeing that, per the labels, blue and red loctite somehow had the same heat rating.
There are multiple red and blue loctites. Red 271 is the one suggested. Good to 500-600⁰ iirc.
But yeah I use rocksett. It's good from -350 to 2000⁰
https://www.trajectoryarms.com/product/gas-block-set-screws/
My word, thank you for the link. I always cringe at spending money for hazardous chemicals (loctite, etc.) or other one-time-use tools, knowing that I might use it once and have a bunch left over.
Ok, a little update. The knurled screws and loctite came. I took the upper apart, but could not get the gas block screws off. So I just blew through the barrel and tube, everything felt good and secure. Last night I got out to a range and only had an hour to work. The 18" + Rifle length tube did not cycle very well with my 4.2oz buffer; switching to a 2.1oz buffer, and she ran like a charm.
Shooting indoors with a mask sucks; my glasses kept fogging up. Will try to upload pics later.
What buffer(s) are you using. 4.2 and 2.1oz sounds very unusual. Is it an adjustable weight buffer?
An 18" rifle length should cycle an H buffer without issue. But if it runs reliably I guess there isn't reason to change it.
yeah, we see gas blocks that need to be put to the torch to heat them up, you mallet tap them into place, and as they cool, they contract tight unto the barrel. Normally only see that with like the primo stuff. about 200 degrees normally gets them on. And once they are on, they certainly dont ever leak.I've ran into an issue that I am not sure where to go with it.
My gas block is a .750 gas block. My understanding was that my barrel has a .750 gas block seat. I can't hand fit the gas block over it, it just stops and feels like you need a hammer to get it on.
I measure them.... the gas block is a .749 and the gas block seat?... .758. FUCK. I wonder if this is something a gunsmith could get to work by like working off some of the finish on my barrel or something.
@Roaming East you ever run into something like this? The gasblock is a BCM and the barrel is Rainier Arms so they're reputable companies. The gas block is close enough but the seat is off by 8 thousandths which seems pretty big when you start thinking about how tight these tolerances tend to be.
Awesome thanks.yeah, we see gas blocks that need to be put to the torch to heat them up, you mallet tap them into place, and as they cool, they contract tight unto the barrel. Normally only see that with like the primo stuff. about 200 degrees normally gets them on. And once they are on, they certainly dont ever leak.