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In the time of Covid, it has been an absolute pain to get parts for builds, so my planned CMP Service Rifle build has been sitting on back order for some time. I finally got all the parts on Friday to complete it, so here it is with specs and test fire groups. I was simultaneously building the cheapest rifle I could with spare parts and whatever I could get my hands on, and the quality difference is astounding, specifically how terrible Bear Creek Arms compares to the other builds I have done. Ill review that one when ammo is a bit easier to come by. Without further ado, here is the completed project.
I started with a Ruger AR 556 lower, which is the most expensive lower I have ever used as a project build. I purchased this lower with the service rifle competition in mind several years ago, and even during that time it ran me $130 before taxes stripped. It does have a very nice finish on it, a duller and more textured finish than my M&P, with a much more aggressively beveled magazine well and very tight tolerances overall. For instance, the accu-wedge between upper and lower is a whopping .1" thick and without it there is still very little play between the upper and lower receiver.
Parts were mainly sourced from JoeBob and Right to Bear. The trigger and lower parts kit is the RTB NiB mil spec with Kaw Valley reduced spring kit and JoeBob sear set screw, the upper is a ZRO Delta, the bolt is the NiB toolcraft, buffer tube from Colt, Matrix arms rail, and Ballistic Advantage Hanson 18" nitride 5.56 barrel with mid length gas system, and includes a really nice low profile pinned gas block. All in all, the finish on everything matched the Ruger lower very well with the exception of the Matrix rail. It has a much grayer appearance, and contrasts with every other anodized part. I don't care all that much, but from an aesthetics standpoint that is a concern.
Mounting Mlok accessories is tough on this rail system, it really hugs the barrel and has marginal clearance around the gas block. I had to cut the MagPul rail screws down so that they would not contact the gas block after attaching a length of rail to the handguard. The barrel nut and assembly were really easy to work with however, and for the cost ($55) I don't know that there is anything comparable out there.
On to the shooting of Stuff: I used my handy dandy backpack bench rest for zero and grouping exercises, not a sand bag or rifle rest, so with that in mind here are the results. The scope used was my Bushnell 1-4 LVPO BTR-1 which I reviewed here: www.northwestfirearms.com/threads/bushnell-btr-1-4-review.349909/. All rounds were fired from 100 yards at the bench with the exception of the zero confirmation exercises in sitting and prone positions with sling.
Lake City 5.56 62 gr Green tip: 2.6" for 5 rounds
Norma Tac .223 55 gr FMJ: 2.1" for 6 rounds
Federal American Eagle .223 55 gr FMJ: 3.2" for 5 rounds
Frontier 5.56 55 gr FMJ: 1.4" for 4 rounds, 1 flier 4" outside (was not me I swear, not sure what happened there)
Frontier 5.56 55 gr FMJ: 1.7" for 5 rounds in sitting, 2.3" for 5 rounds in prone.
I have used the Frontier 5.56 in 55 and 75 grain extensively for CMP and NRA high power as they have always been the most consistent factory ammo for me at bulk price. They are not match branded, and though I have used the Frontier match, my group size did not appreciably shrink for the added cost (maybe down to sub 1" groups consistently for twice the cost). I had no malfunctions throughout the day, and was hitting the center bull after 3 rounds with the lake city ammo during zero. The Norma was the slowest ammo to cycle the rifle, but that should be expected with the .223 load. Ejection was great at about the 4 o'clock and out to 8ish feet.
The trigger weight feels about right at the rated 6 lbs, and is very crisp. The trigger movement is only .08" with a solid reset. Again I am really impressed with the Bushnell scope, I went through everything from rain to full on breaks of sun and it was very clear in all conditions. The mil adjustment is not ideal, so doing math of inches to mil clicks will be an issue at 600 yards during the CMP, but it is very close to 3 clicks an inch at 100 Yards.
For a purpose built rifle, this one feels like a winner. I didn't get the overall weight yet, but it's in the 8.5ish pound range. It handles like a carbine (no surprise there) and the only complaint I have is the Colt end plate with sling attachments bites into my thumb when operating the safety. The 18" Hanson profile barrel is a winner in my book, and though I would have preferred the .223 wylde chamber I much prefer the nitride barrel finish that comes on the 5.56. I usually compete once a month all year with a few regional or state matches thrown in, so this is going to see some serious use in all weather conditions and having a protective finish on the barrel is great.
I'll be testing out some hand loads in this rifle later, but I am very pleased with how it worked out for the cost. I am into the finished rifle without optic for about $1,100 which I feel is reasonable for what it is.
I started with a Ruger AR 556 lower, which is the most expensive lower I have ever used as a project build. I purchased this lower with the service rifle competition in mind several years ago, and even during that time it ran me $130 before taxes stripped. It does have a very nice finish on it, a duller and more textured finish than my M&P, with a much more aggressively beveled magazine well and very tight tolerances overall. For instance, the accu-wedge between upper and lower is a whopping .1" thick and without it there is still very little play between the upper and lower receiver.
Parts were mainly sourced from JoeBob and Right to Bear. The trigger and lower parts kit is the RTB NiB mil spec with Kaw Valley reduced spring kit and JoeBob sear set screw, the upper is a ZRO Delta, the bolt is the NiB toolcraft, buffer tube from Colt, Matrix arms rail, and Ballistic Advantage Hanson 18" nitride 5.56 barrel with mid length gas system, and includes a really nice low profile pinned gas block. All in all, the finish on everything matched the Ruger lower very well with the exception of the Matrix rail. It has a much grayer appearance, and contrasts with every other anodized part. I don't care all that much, but from an aesthetics standpoint that is a concern.
Mounting Mlok accessories is tough on this rail system, it really hugs the barrel and has marginal clearance around the gas block. I had to cut the MagPul rail screws down so that they would not contact the gas block after attaching a length of rail to the handguard. The barrel nut and assembly were really easy to work with however, and for the cost ($55) I don't know that there is anything comparable out there.
On to the shooting of Stuff: I used my handy dandy backpack bench rest for zero and grouping exercises, not a sand bag or rifle rest, so with that in mind here are the results. The scope used was my Bushnell 1-4 LVPO BTR-1 which I reviewed here: www.northwestfirearms.com/threads/bushnell-btr-1-4-review.349909/. All rounds were fired from 100 yards at the bench with the exception of the zero confirmation exercises in sitting and prone positions with sling.
Lake City 5.56 62 gr Green tip: 2.6" for 5 rounds
Norma Tac .223 55 gr FMJ: 2.1" for 6 rounds
Federal American Eagle .223 55 gr FMJ: 3.2" for 5 rounds
Frontier 5.56 55 gr FMJ: 1.4" for 4 rounds, 1 flier 4" outside (was not me I swear, not sure what happened there)
Frontier 5.56 55 gr FMJ: 1.7" for 5 rounds in sitting, 2.3" for 5 rounds in prone.
I have used the Frontier 5.56 in 55 and 75 grain extensively for CMP and NRA high power as they have always been the most consistent factory ammo for me at bulk price. They are not match branded, and though I have used the Frontier match, my group size did not appreciably shrink for the added cost (maybe down to sub 1" groups consistently for twice the cost). I had no malfunctions throughout the day, and was hitting the center bull after 3 rounds with the lake city ammo during zero. The Norma was the slowest ammo to cycle the rifle, but that should be expected with the .223 load. Ejection was great at about the 4 o'clock and out to 8ish feet.
The trigger weight feels about right at the rated 6 lbs, and is very crisp. The trigger movement is only .08" with a solid reset. Again I am really impressed with the Bushnell scope, I went through everything from rain to full on breaks of sun and it was very clear in all conditions. The mil adjustment is not ideal, so doing math of inches to mil clicks will be an issue at 600 yards during the CMP, but it is very close to 3 clicks an inch at 100 Yards.
For a purpose built rifle, this one feels like a winner. I didn't get the overall weight yet, but it's in the 8.5ish pound range. It handles like a carbine (no surprise there) and the only complaint I have is the Colt end plate with sling attachments bites into my thumb when operating the safety. The 18" Hanson profile barrel is a winner in my book, and though I would have preferred the .223 wylde chamber I much prefer the nitride barrel finish that comes on the 5.56. I usually compete once a month all year with a few regional or state matches thrown in, so this is going to see some serious use in all weather conditions and having a protective finish on the barrel is great.
I'll be testing out some hand loads in this rifle later, but I am very pleased with how it worked out for the cost. I am into the finished rifle without optic for about $1,100 which I feel is reasonable for what it is.
