Getting some conflicting information on build tools

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freewheeling

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From what I've read an upper action block is a better way to secure things when adding or changing a barrel than a barrel clamp, so I ordered a DPMS Panther Claw in anticipation of working on my build. (I currently have a complete lower, including stock.) Then some guy on the AR.15 site said that action blocks harm the rifle and that the Panther Claw has been shown to damage uppers. He also said that the sized spanner castle wrenches I have should be relied on and that I should buy the special armorers tool.

I can't figure out how to use the AR15 site or even find the thread where that was posted (it's very opaque to the user) so decided to ask the questions here. First, all of the comments I've seen say that the Panther Claw is a great tool and I haven't seen any complaints of problems, but are there any? Would I be better off cancelling that order and getting a clamshell barrel clamp of some sort? They're certainly cheaper.

About the Armorer's tool I have a retention device that works like a big set of snap-ring pliers, and a 5-size castle nut wrench. I've already used it to tighten the nut on the buffer extension and it worked fine. I figure that the two together should work on the barrel too. I can at least try it, and if it look sketchy I can always order an armorer's tool from Amazon Prime. They seem to have a lot of them.

I was also going to order some steel roll pin punches and a brass/nylon hammer, and a lower vice block which just looks like a solid nylon mag that locks into a bench vice (pretty cheap). Should I bypass the steel roll pin punches and just get brass?

Here's a pick of the two S&S coupler tools, the wrench and the retention tongs.

IMG00027-20130413-2136.jpg
 
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I guess there are no ideas, huh? Well, I'll wait until I get the parts and have to install the barrel nut. I may get a Seekins, in which case I wouldn't even need a barrel nut wrench, but looking at the conventional nut in pictures just about any sort of notched wrench would work. The only issue is whether or not I could get enough torque on it to get it tight. I'm pretty sure the tongs would be good for installing a floating hand rail, but I can always order the wrench if things don't work.
 
I've got a wheeler upper vice block and a wrench from aim sports. They work for me.
 
I think roll pin punches woul be nice but I have used random small punches and sections of brass rod from the hardware store. I smoothed the edges of the rod so it won't marr anything. I use the proper size nail set punch for taper pins. The key is to use a punch just big enough to cover the head of the pin. Also I find that using a longer punch or section of brass rod is handy for driving the bolt catch roll pin with the receiver setting vertical on its nose.
 
Freewheeling-

A lot depends on how mechanically savvy you are-

I have built uppers and lowers without using a single specialty tool- not even a torque wrench- but I have a long professional history of taking things apart and putting them back together to work with...

I've never used a hammer assembling an AR, preferring to use a pair of water pump pliers ('Channel Locks') as a press, and often using a set of allen keys in the place of punches.

While the right tools DO make the job easier- especially for a neophyte, spending a hundred bucks on tools you will likely use only once doesn't make a lot of sense- especially as I would bet you could come up with someone local who has some tools they'd lend.

I see you're in VA- if you are anywhere around me (Chesapeake/Norfolk/etc.,) I'd be happy to lend you an armorer's tool and give you a hand with assembly.
 
Armorer's wrenches can be had for under $30, so no reason to fight with improper tools there. The castle nut on the buffer tube and the barrel nut are two totally different animals, and it's doubtful you'll get sufficient torque on the barrel nut without damaging it using the spanner wrench you've pictured. 50 ft lbs is a good base number (spec is 30-80), but I've had to make many of them substantially tighter to get everything lined up.

As for receiver clamping, yes, some of the pin blocks and clam shells can lead to a torqued upper if you end up having to use quite a bit of force on the barrel nut. I use soft pine blocks. On a flat top, I'll clamp the upper in a vise laying down, and tighten it until the picatinny rail and bottom edges of the receiver are decently embedded in the wood. I also put a piece of 1/2" steel stock between the sides of the upper to keep it from bending; I learned the hard way on this one, having not used the piece of steel inside the upper on one of my first builds and tweaking the receiver. With creative use of an 4 ton hydraulic spreader, I was able to straighten it, but the lesson was taken.

If you're going to use a clam shell, get one that substantially envelopes the receiver and has a piece that inserts into the receiver; without that insert, you may well end up with the right side bent inward at the bottom.

Also, put oil on the threads. If you get it torqued and have to go just a touch further, breaking the friction lock on dry threads to get that last couple degrees of movement will take tremendous torque.
 
I bought the Brownell clam shell action block....I had to torque my barrel to 60 ft-lb. and my upper did not suffer at all.

The military manual actually calls for grease on the receiver threads...but some people use nothing at all...grease or oil is a good idea IMO.

The manual also states you should tighten to 30 or 32 ft-lb, loosen the barrel nut, tighten to 30 or 32 ft-lb loosen the barrel nut again, and then tighten to barrel nut until the holes on the barrel nut line up with the hole on the receiver through which the gas tube will pass....hopefully it won't take all 80 ft-lb to do that.

I would not use the action block which just holds the receiver by the takedown holes....

I would just go ahead and get an armorer's tool. One that has something to tighten the barrel not and the receiver extension lock nut. I didn't worry about torquing the lock nut...but torquing the barrel was important to me.

best advice I can give you is, lube your roll pins...
 
Thanks for the advice. I think I've decided to build or buy an Adams piston system. I may have to use other parts and then use their conversion kit, so if I go with the Seekins upper it uses a titanium barrel nut that just has flat sides so you use an ordinary 9/8ths wrench. I used to have a torque wrench somewhere but must've left it behind in one of my moves. Should probably get one.

Have already ordered the action block, but it would probably be easy to sell on ebay if I don't use it. I guess the incremental modular plan is sort of like a layaway program. Just get the parts I can afford when I can afford them. Will post pictures when I get them. Meanwhile, here's the upper such as it is.

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I use a PRI vice block and it works great. It pins into your lower via the take-down pin holes. If you are installing a new barrel on a stripped upper I wouldnt worry about deforming your upper. Excessive force and a twisted upper is usually the result of removing a stubborn barrel. Those all in one armorer tools sometimes have the wrench cutout farther down the handle which would increase leverage and magnify torque. Your torque wrench should be as close to the barrel nut as possible.
 
Excessive force and a twisted upper is usually the result of removing a stubborn barrel.

I love my Armalites, but I was a little perturbed at the amount of torque on my M15's barrel nut. After using the armorer's wrench in conjunction with an air hammer (pickle fork fit into the flash hider notch) to no avail, I ended up having to heat the nut with an oxy-acetylene torch and use the air hammer with a chisel to bust it loose. I'm guessing it would have taken well in excess of 400 ft lbs to loosen it without heat and impact, which would have pretzeled the upper. With heat, the upper & barrel were OK, but nut and delta ring were totally destroyed. Didn't matter, though, since I was installing a FF quad rail.

Note: I don't suggest the use of such heat for this purpose unless you're experienced with torches in this capacity. Heating it too slowly or not being quick about getting the parts separated could anneal the upper or even the barrel, causing them to loose their temper and fail. I know how to blow hardened steel studs out of blind holes in cast iron without killing the threads, but that skill didn't come over night, and I destroyed a lot of pieces in learning.
 
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From what I've read an upper action block is a better way to secure things when adding or changing a barrel than a barrel clamp, so I ordered a DPMS Panther Claw in anticipation of working on my build. (I currently have a complete lower, including stock.) Then some guy on the AR.15 site said that action blocks harm the rifle and that the Panther Claw has been shown to damage uppers. He also said that the sized spanner castle wrenches I have should be relied on and that I should buy the special armorers tool.

I have used the Panther Claw, and I think it is a great option. It fits securely into the recess at the top of the upper for the charging handle, and the bottom side fits into the takedown pin holes. So when you torque that barrel nut, you have contact at the charging handle slot, the lower opening of the receiver, and at both takedown pin holes. I think that is a pretty good distribution of force across the upper. They also work with pretty much any upper - A2, slicksides, left handed, etc. The clamshells only work well if they fit well.

As to that tool for the barrel nut, I think I would pass. Definitely would pass if replacing the barrel nut meant removing a pressed on FSB. The teeth on the barrel nut are relatively soft. I would recommend a good armorers wrench, in this environment you will likely not lose much money on either a Panther claw or armorers wrench if you do not keep it after your build.
 
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