My goal here was to do a build focused on affordable precision to meet my need for a general purpose sporting rifle. I wanted something that would work well for varmints and longer range paper punching but without a bull barrel to facilitate shooting offhand with iron sights. I feel like I did a pretty good job of meeting that goal, despite the fact that it is not as high-zoot as many of the rigs some of you folks are shooting. Anyway, I enjoyed the heck out of gathering the parts and building it, and I am happy with the outcome. My hope is that I can sell off some of my other AR stuff as I get this one ironed out, and this can become my go-to AR for varmints, plinking, etc.
Here is the parts and cost breakdown:
DSA Lower from the local shop - $140
DPMS slick side upper - $75 (went with this because I don't need forward assist or a dust cover, and I like the heavy wall construction combined with a low profile. Fits the lower very nicely, the pins slide in easily, but there is almost no wobble at all)
DPMS LPK $50
JP spring kit $10
Del-ton Buttstock $55
Magpul Grip $35
DPMS DCM Barrel $240
Gas tube $15
DPMS vented free float tube $80
Bolt/Carrier Assembly (using a del-ton from another upper temporarily, but I will order a basic BCM for it soon, so $135)
Total in the rifle - $835
Scope Mount $33 (NCstar... Yeah, I know, but I wanted a quick release unit so I could alternate to iron sights more easily. I have a riser block that I might use if this thing is junk, or I will order a larue mount, but I thought I would give this a try. I can just sell it at the next fun show if I am not impressed. But, it actually locks on pretty well, so it might work out.
Tasco Varmint 6-24x mil-dot Scope $80 (already had it sitting from another project, and is just a place holder while funds build back up for better optics)
Detachable carry handle $45 (I really like shooting with irons)
Bipod $40
So, as you see it in the finished picture at the end, I have right around $1000 in it, which was my budget. Once I upgrade the trigger and optics as I have the funds, I will be over that, but oh well...
The Lower:
Nothing terribly fancy here. I built this about a year ago and was using it with a different upper. The only upgrades to this were the magpul grip, a 15 minute trigger job, and the JP Enterprise springs. The trigger job consisted of putting valve lapping compound on the sear surface and dry firing it about 50 times (adding a little more compound every so often). Then I disassembled the trigger group, cleaned it up, and reassembled it using some moly grease on the pins, and on the sear surface, and using the lighter springs. The trigger used to be horrible, it is still horrible but lighter. I tried to go cheap on the trigger, and am unsatisfied not surprisingly. But it cost $10, and it is easy to swap out, so now I am trigger shopping. Suggestions?
The Upper Build:
First order of business was to square the front of the receiver using a mandrel from Brownells and some valve lapping compound. It only took a second because it was really close to begin with.
Next, (after cleaning up from step 1), I slid the barrel into place, put some moly grease on the receiver threads, snugged up the barrel nut 3 times, torqued it to 30 ft. lbs. then tried to move it to the next gas tube hole. It was going to take over 80 ft. lbs. to get there, so I took it all back apart and gave the receiver face another go with the mandrel and lapping compound. Cleaned up, and reassembled, I got the gas tube holes aligned with 60 ft. lbs.
I then assembled the float tube, using some moly grease on those threads too, and installed the front sight base and gas tube. The front sight base on these DCM barrels doesn't have taper pins, it uses four set screws that come in from the sides so that windage can be adjusted with the front base to center the rear sight. Although I like that from the perspective of ensuring maximum windage adjustment availability from the rear sight, I like it even more because there are no set screws or taper pins pressing on the barrel in a way that could distort the bore. I don't know if that is really a concern, but I have read that it is, and I can see how it might be.
The hand guard didn't have a place for a sling mount, so I drilled one.
Then, I dropped in the bolt/carrier group and charging handle, and attached the lower, clamped on the scope, hooked the bi-pod on, and here she is:
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I haven't fired it yet, but I hope to this weekend! All in all, I am a happy camper. It balances very nicely with the carry handle on and the bipod gone, should be great for shooting with irons. I will update this with more pictures and a range report when I get a chance.
If the picture isn't showing up, let me know, this was my first attempt at posting a picture!