Part 1
I have repeatedly been asked my opinion on Black Hole Weaponry barrels, particularly once people realized that it was a local business to me. Unfortunately, my personal experience was limited to my 16" 5.56 barreled carbine. About 8 months ago I was offered the chance to purchase a new Black Hole Weaponry 16" barrel at dealer cost. This would not be a Grendel chamber, but a Les Baer .264 barrel. This barrel actually had the same profile as the 16" 5.56 barrel in my competition gun, and I thought it would be an interesting match. I received the barrel/bolt in late July and its been sitting in my safe since. I did double check that it was a Grendel spec bolt, not the shallow .125 version typically used for 7.62x39.
Late last year I began hearing rumors that Precision Firearms had developed their own billet upper and lower, and after some very enlightening discussions Mark agreed to let me buy a set, along with his lower parts kit. Mark is a joy to talk with, and very gracious in answering questions about his company, parts, and building an AR, whether its yours or his.
Mark had provided some of the parts on a previous 5.56 build, giving me great advice about a carbon fiber handguard from Lancer that I ended up using and really liking. He told me this time about a handguard from Geissele, (yes, the trigger people!) that he had been using and really liked. I asked him to send one of those along as well. http://geissele.com/15-super-modular-rai...black.html
Last week the parts arrived, and after inspecting the separately packed upper and lower, I began unpacking everything else. Once I had all the parts out, I again closely inspected each individual piece, and them started dry mating them with the other pieces I would be using.
It immediately became obvious that this was the tightest upper/lower match I had ever had the pleasure of manipulating. The two pieces fit together so well that when I closed my eyes and tried to feel the seam where they came together I could only identify it accurately by feel about 1/2 the time. The finish on the parts was impeccable, with nary a ding or lost anodizing anywhere, not even on the sharper than normal edges of the brass deflector, an area where even milspec, rounded surfaces often lose anodizing. The fit was snug enough that I could hold the upper and the lower would not fall free. Flipping it over, the upper would not fall off the lower, either. This caused some concern, because disassembly can become problematical if the match is this tight BEFORE there were pins in it. I searched in vain for tooling marks. There simply aren't any that I could find, even in the hard to reach and seldom seen places like the inside of the rail above the charging handle. No swirls, no linear marks, no nothing.
I moved on to the forearm and barrel nut. Geissele has chosen to go another route, and where many companies continue with the traditional barrel nut or some variation, Geissele has created a tubular bearing with 3 separate journals that is threaded inside to fit over the uppers threading, locking the barrel extension in place and providing several inches of support to the hand guard. The instructions say that using a small amount of lubricant might be helpful, as the fit is just .001 difference in ID of the handguard and the OD of the bearing. The instructions strongly caution that the fit should be snug, but not impossible to manipulate by hand. After attempting a true dry fitting, I put a few drops of Lubriplate FMO-AW 350-AW oil on each of the 3 journals, and the handguard slid nicely into place. I disassembled the pieces and went to work finding the rest of the parts I would need, including the proper gas block, which I had neglected to tell Mark I would need.
Once I had all the parts together Saturday afternoon, I began assembling the upper. The trial run dry fitting all the parts was very helpful, and the upper was together in little more than 30 minutes, with all the proper torque specifications. Geissele recommends using 40 foot pounds on the barrel nut bearing, but points out that AR's have been built for decades without any specific torque numbers in wide use and most of them shoot very reliably. The gas block screws were torqued to 20 inch pounds, and the two bolts securing the handguard to the 5 foot pounds recommended. These two bolts fit beneath the journal gaps on the bearing surface and mate with two nuts pressed into the opposite side of the upper before shipping.(Note to the wise....Pay attention to FOOT POUNDS vs INCH POUNDS!) Try to torque those little gas block screws to 20 foot pounds and you'll ruin the screws, the block, or both!
With the upper assembled, I pulled out a couple parts kits and grabbed the Precision Billet Lower and a Spikes tactical forged lower I had in the safe. With my adult son, we began a side by side build of the two, using Precision Firearms lower parts kits. (I've found that you can build a lower with 2 hands, but that a third or fourth hand can be very helpful at a couple steps!)
The Precision lower went together like butter, with every part fitting correctly and without binding or problem. This again confirmed Precision Firearms attention to detail, every hole was precisely the right size, with no flashing or rough areas. The Spikes tactical forged lower was almost as good, though we had a couple very minor issues with alignments. They were within spec, but just not quite as perfect as Precisions Billet.
I have repeatedly been asked my opinion on Black Hole Weaponry barrels, particularly once people realized that it was a local business to me. Unfortunately, my personal experience was limited to my 16" 5.56 barreled carbine. About 8 months ago I was offered the chance to purchase a new Black Hole Weaponry 16" barrel at dealer cost. This would not be a Grendel chamber, but a Les Baer .264 barrel. This barrel actually had the same profile as the 16" 5.56 barrel in my competition gun, and I thought it would be an interesting match. I received the barrel/bolt in late July and its been sitting in my safe since. I did double check that it was a Grendel spec bolt, not the shallow .125 version typically used for 7.62x39.
Late last year I began hearing rumors that Precision Firearms had developed their own billet upper and lower, and after some very enlightening discussions Mark agreed to let me buy a set, along with his lower parts kit. Mark is a joy to talk with, and very gracious in answering questions about his company, parts, and building an AR, whether its yours or his.
Mark had provided some of the parts on a previous 5.56 build, giving me great advice about a carbon fiber handguard from Lancer that I ended up using and really liking. He told me this time about a handguard from Geissele, (yes, the trigger people!) that he had been using and really liked. I asked him to send one of those along as well. http://geissele.com/15-super-modular-rai...black.html
Last week the parts arrived, and after inspecting the separately packed upper and lower, I began unpacking everything else. Once I had all the parts out, I again closely inspected each individual piece, and them started dry mating them with the other pieces I would be using.
It immediately became obvious that this was the tightest upper/lower match I had ever had the pleasure of manipulating. The two pieces fit together so well that when I closed my eyes and tried to feel the seam where they came together I could only identify it accurately by feel about 1/2 the time. The finish on the parts was impeccable, with nary a ding or lost anodizing anywhere, not even on the sharper than normal edges of the brass deflector, an area where even milspec, rounded surfaces often lose anodizing. The fit was snug enough that I could hold the upper and the lower would not fall free. Flipping it over, the upper would not fall off the lower, either. This caused some concern, because disassembly can become problematical if the match is this tight BEFORE there were pins in it. I searched in vain for tooling marks. There simply aren't any that I could find, even in the hard to reach and seldom seen places like the inside of the rail above the charging handle. No swirls, no linear marks, no nothing.
I moved on to the forearm and barrel nut. Geissele has chosen to go another route, and where many companies continue with the traditional barrel nut or some variation, Geissele has created a tubular bearing with 3 separate journals that is threaded inside to fit over the uppers threading, locking the barrel extension in place and providing several inches of support to the hand guard. The instructions say that using a small amount of lubricant might be helpful, as the fit is just .001 difference in ID of the handguard and the OD of the bearing. The instructions strongly caution that the fit should be snug, but not impossible to manipulate by hand. After attempting a true dry fitting, I put a few drops of Lubriplate FMO-AW 350-AW oil on each of the 3 journals, and the handguard slid nicely into place. I disassembled the pieces and went to work finding the rest of the parts I would need, including the proper gas block, which I had neglected to tell Mark I would need.
Once I had all the parts together Saturday afternoon, I began assembling the upper. The trial run dry fitting all the parts was very helpful, and the upper was together in little more than 30 minutes, with all the proper torque specifications. Geissele recommends using 40 foot pounds on the barrel nut bearing, but points out that AR's have been built for decades without any specific torque numbers in wide use and most of them shoot very reliably. The gas block screws were torqued to 20 inch pounds, and the two bolts securing the handguard to the 5 foot pounds recommended. These two bolts fit beneath the journal gaps on the bearing surface and mate with two nuts pressed into the opposite side of the upper before shipping.(Note to the wise....Pay attention to FOOT POUNDS vs INCH POUNDS!) Try to torque those little gas block screws to 20 foot pounds and you'll ruin the screws, the block, or both!
With the upper assembled, I pulled out a couple parts kits and grabbed the Precision Billet Lower and a Spikes tactical forged lower I had in the safe. With my adult son, we began a side by side build of the two, using Precision Firearms lower parts kits. (I've found that you can build a lower with 2 hands, but that a third or fourth hand can be very helpful at a couple steps!)
The Precision lower went together like butter, with every part fitting correctly and without binding or problem. This again confirmed Precision Firearms attention to detail, every hole was precisely the right size, with no flashing or rough areas. The Spikes tactical forged lower was almost as good, though we had a couple very minor issues with alignments. They were within spec, but just not quite as perfect as Precisions Billet.
You seek escape from pain. We seek the achievement of happiness. You exist for the sake of avoiding punishment. We exist for the sake of earning rewards. Threats will not make us function; fear is not our incentive. It is not death that we wish to avoid, but life that we wish to live. - John Galt
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