Install new barrel without action block?

moonshine44

moonshine44

Active member
Is it possible to do that without wrecking something important, like the upper? I'm going to be installing my new BHW barrel to a new upper, but I don't have an action block. Is there a way to do it by improvisation?

Thanks!
 
Maybe some boards lined with styrofoam to clamp it in vise but as stated above its probably not a very good idea.

Ive never assbled on myself but the way i understand that upper vise block is used to not only protect the upper but more importantly to allow the pressure to be applied to the "correct" areas on the reciever.

I dont see anyway around it cept to get the upper block and i dont think the savings are worth the risk. Plus if you just buy the right tools you will be able to properly assemble more in the future
 
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You do not need an action block. All you need is a good vice. I use two half inch thick pieces of polyethylene taped over the jaws(Hardwood like oak will also do). I chuck it in the vice sideways so the picatinny rail and the bottom of the upper receiver are the surfaces in contact with the polyethylene. Don't over do it. For assembling AR's you should at minimum have an armorers wrench, torque wrenches in inch and foot lbs, and moly anti seize grease in addition to common tools.

If you don't have much gunsmithing experience then an action block might be the way to go. Mistakes are expensive.
 
Originally Posted By: mj36639You do not need an action block. All you need is a good vice. I use two half inch thick pieces of polyethylene taped over the jaws(Hardwood like oak will also do). I chuck it in the vice sideways so the picatinny rail and the bottom of the upper receiver are the surfaces in contact with the polyethylene. Don't over do it. For assembling AR's you should at minimum have an armorers wrench, torque wrenches in inch and foot lbs, and moly anti seize grease in addition to common tools.

If you don't have much gunsmithing experience then an action block might be the way to go. Mistakes are expensive.

Bought an action block for my first build but my LAR ops-4 upper did not fit in it. I did just as described above making sure that the vise was clamped on the very front of the upper because it looked like there was the most metal there and it was closest to the barrel. It seemed fine and I was able to put 40 foot pounds of torque on the barrel nut.

I cut a .5 inch thick plastic cutting board for the jaw pads. I would just be careful not to tighten the upper any more that snug.
 
Originally Posted By: mj36639You do not need an action block. All you need is a good vice. I use two half inch thick pieces of polyethylene taped over the jaws(Hardwood like oak will also do). I chuck it in the vice sideways so the picatinny rail and the bottom of the upper receiver are the surfaces in contact with the polyethylene. Don't over do it. For assembling AR's you should at minimum have an armorers wrench, torque wrenches in inch and foot lbs, and moly anti seize grease in addition to common tools.

If you don't have much gunsmithing experience then an action block might be the way to go. Mistakes are expensive.

Mj, why the need for an in/lbs torque wrench? I've put together 3 ARs from scratch and have never needed this tool. I'd spend the money on a proper action block before I'd even think of an in/lbs torque wrench for an AR.

To the OP - just spring for the action block. It will make things so much easier and it is the right way to do it. You'll kick yourself for not spending the 30 bucks or so if you ruin a 100 dollar upper, especially after trying to find one to replace it. You can always rent it out too, I've always believed good tools pay for themselves.
 
The clamp comes with a insert that fits inside the upper so you don't deform it. I would get the tools. It won't be the last upper you build and it will be a good investment. One ruined stripped upper receiver will cost you twice what you will pay for the tools to do it the right way...
 
Originally Posted By: mj36639You do not need an action block. All you need is a good vice. I use two half inch thick pieces of polyethylene taped over the jaws(Hardwood like oak will also do). I chuck it in the vice sideways so the picatinny rail and the bottom of the upper receiver are the surfaces in contact with the polyethylene. Don't over do it.

I've installed over 2 dozen barrels using a method very similar to this. Never damaged any of them.
 
Looks like it's the proverbial "six of one, half a dozen of the other", don't it?
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Well, I do have a credit at Joebob's, so maybe I'll go ahead and use it and get the right tools. I have a barrel nut wrench, so I'm good there...

Thanks, guys!
 
Originally Posted By: goose_boyOriginally Posted By: mj36639You do not need an action block. All you need is a good vice. I use two half inch thick pieces of polyethylene taped over the jaws(Hardwood like oak will also do). I chuck it in the vice sideways so the picatinny rail and the bottom of the upper receiver are the surfaces in contact with the polyethylene. Don't over do it. For assembling AR's you should at minimum have an armorers wrench, torque wrenches in inch and foot lbs, and moly anti seize grease in addition to common tools.

If you don't have much gunsmithing experience then an action block might be the way to go. Mistakes are expensive.

Mj, why the need for an in/lbs torque wrench? I've put together 3 ARs from scratch and have never needed this tool. I'd spend the money on a proper action block before I'd even think of an in/lbs torque wrench for an AR.

To the OP - just spring for the action block. It will make things so much easier and it is the right way to do it. You'll kick yourself for not spending the 30 bucks or so if you ruin a 100 dollar upper, especially after trying to find one to replace it. You can always rent it out too, I've always believed good tools pay for themselves.

I use an foot lbs torque wrench to tighten the barrel nut and an inch lbs torque wrench to tighten the flash suppressor. I use these tools because I assemble my rifles following Army Technical Manual 9-1005-319-23&P.

The manual dictates 30 foot lbs to mount the barrel with a maximum of 80 foot lbs for final barrel alignment and 15-20 inch lbs to properly index the flash suppressor using peel washers. Now if you use crush washers or a different style flash suppressor like the Vortex then the Inch lbs torque wrench is not needed; because the Vortex does not use washers and crush washers do not have a specified torque setting.

I deviate from the manual in regards to the action block because AR-15/M-16 action blocks were designed prior to the flat top picatinny rail M-4 upper receiver. When the rifle had a built in carry handle the receiver only had one flat surface. Current upper receivers have two.

Can you assemble an AR without the proper tools? Sure you can. That doesn't mean it's a wise thing to do. We are both advocating deviations from the Army TM. However my method ensures all of the correct assembly specifications are maintained.

The torque wrenches are also invaluable tools to ensure proper torque values are achieved when mounting scope rings and bases.
 
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If you have the money and it eases your mind, by all means get an action block & do it "correctly."

That being said, two pieces of wood and an adequate vise is all I've ever used for changing out barrels/handguards on flat top uppers.

I just use a strip of 1/2" thick plywood to protect the top (rail) side of the receiver from one vise jaw. I use a 2x4 with two holes drilled in it for the hinge pin extensions to sink in to, so the bottom of the receiver sits flush against the 2x4 which then protects the bottom of the receiver from the other vise jaw. Just sandwich it all together in the vise and it gives a rock solid hold, protects the receiver from any damage, and costs about 50 cents???...done several barrels/handguards using the same two pieces of wood over the years.
 
There is no need for ft/lbs wrenches if you can do math. 30-80 ft/lbs is 360-960 in/lbs. Also, torque wrenches are not overly expensive. I've used some from Harbor Freight and used the same testing/calibration procedures that we use in the AF for use on aircraft. They hold true and dont break the bank.

A good AR wrench is a bit spendy, but worth it. The cheaper one will either break during usage or wreck the component you are trying to tighten/loosen. I prefer a traditional open end wrench for muzzle devices. But that is just a preference thing.

The 2X4 with holes drilled for the mounting studs sounds like a great idea. More surface contact is going to be more stable and secure. And I see a lower likelyhood of damage with this method.

So...no...and action block isnt needed.
 
Originally Posted By: pahntr760There is no need for ft/lbs wrenches if you can do math. 30-80 ft/lbs is 360-960 in/lbs. Also, torque wrenches are not overly expensive. I've used some from Harbor Freight and used the same testing/calibration procedures that we use in the AF for use on aircraft. They hold true and dont break the bank.

A good AR wrench is a bit spendy, but worth it. The cheaper one will either break during usage or wreck the component you are trying to tighten/loosen. I prefer a traditional open end wrench for muzzle devices. But that is just a preference thing.

The 2X4 with holes drilled for the mounting studs sounds like a great idea. More surface contact is going to be more stable and secure. And I see a lower likelyhood of damage with this method.

So...no...and action block isnt needed.

What inch lbs torque wrench are you using? Mine only goes up to 200 inch lbs.
 
I do really like the idea of turning the reciever 90deg in the vice...seem like a very easy solution and with the 2x4 with hole in bottom is just plain brilliant!!

Thanks for the ideas fellas, i was going to purchase the uper block but not anymore!!
 
I have some Snap-On ones that I got through DRMO. mine is 100-1000 in/lbs. I also have an inline screwdriver type that is 0-60 that works great for rings and bases.
 
Originally Posted By: pahntr760I have some Snap-On ones that I got through DRMO. mine is 100-1000 in/lbs. I also have an inline screwdriver type that is 0-60 that works great for rings and bases.

Oh man Snap on makes great stuff, That's a $150+ wrench.
 
You might be able to borrow one if you ask around at local shops or ranges. Maybe get on Facebook and see if there are any local groups that are shooting related.
 
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