Gotm4/Robb’s Project Featherweight thread inspired me to put together a 16” lightweight for my wife using many of the parts listed therein.
Here are the parts used for the assembly:
Lower
• DD lower
• DD LPK (minus FCG) with Magpul polymer trigger guard
• Bill Springfield trigger with JP springs
• M&A parts “Colt” CAR buttstock.
• BCM RE kit, std. buffer
• Noveske QD end plate
• Magpul MOE grip
Upper
• DD 16” mid-length pencil BBL
• VLTOR GB with middy tube
• Micor titanium flash suppressor configured for 1:7 twist BBL
• Troy 11” TRX Extreme rail
• Les Baer upper (no fwd assist provision), stripped
• JP low mass BC with BCM cam pin, firing pin & retaining pin
• BCM bolt
• BCM standard CH
Optics and Accessories
• DD fixed front sight
• Cavalry Arms fixed rear sight
• BFG 1 point UDC sling with QD
• PMAGs, 20 round variety
Items that differed from Project Featherweight were the DD 16” middy pencil barrel, the 0.625” VLTOR GB, the Cav Arms rear sight, Les Bear upper and the Micor titanium FH. The DD barrel is without a doubt heavier than Robb’s contoured 14.5 middy as is the VLTOR GB compared to his heavily modded FSB. The other items included were roughly a few gnat’s asses lighter. The Cav Arms rear sight was 37g versus the 48g for the DD rear. The Les Bear stripped upper was 195g versus 203g for a standard stripped A4 upper and we’re both deleting the ejection port cover and forward assist. I suspect the Schuster plug in Robb’s setup in only a few grams. The flash hider, the Micor titanium piece weighed in at 37g versus 60g for an A1 or A2 FH.
The final weight with BUIS is 84.15 oz or 5 lb, 4.2 oz.
My wife is going to shoot this config for a while and add an Aimpoint H1 at a later date. The weight with the Aimpoint Micro and DD micro mount should be 88.8 oz or 5lb, 8.8 oz.
Thanks to Robb/gotm4 and others who contributed to the Project Featherweight thread.
Thanks. I’m going to sight it in tomorrow and wring it out a bit.
The only potential issue I see with this setup is the balance. The center of mass is very close to the front of the mag well with the stock collapsed. Extending the stock, of course, shifts the weight rearward and the front end becomes quite light. Not really an issue for me, but might be for the wife. I may have to replace the FH with a brake.
The only thing I see is the use of the JP low weight BC and a standard gas block. Maybe you’ll get lucky and it will optimize out, but if I were going to run (and I do) the JP BC I’d want either an adjustable GB or even better a tuned gas port. Most people seem to want to make the BCG heavier, not lighter, in the name of reliability. I’d rather tune it and it may pay dividends in lighter recoil for your wives gun.
I totally agree with using a heavier BCG for ultimate reliability and employ M16 BCGs in all of my SHTF rifles. Given that this is more or less a range/training toy and the fact that Robb seems to be having no issues with his middy I thought I’d give the low mass BC a go. Of course, Robb’s middy is a 14.5" vs. my 16" so my BCG should be receiving more gas pressure. I’ll have to see how it works out using a variety of milspec and commercial ammo.
thanks for reminding me that I need to get busy and put mine together. I identified a potential issue with lighter weight leading to more recoil from the outset and have both a PWS and Rainer FH/brake and am hoping that the 1.5 Battle Comp and the non-mount AAC Brakeout both come out soon (I’m using a 14.5" DD barrel).
Today I shot a 150 round mix of 55gr commercial ammo. No feeding issues and was ejecting brass in a fairly consistent pattern. Recoil was sharp with the stock buffer and better with an H. This is pretty much a non issue for me, however, the muzzle jumps very quickly making quick follow-up shots difficult.
Rob_s, you’re spot on- it definitely needs a brake. I think I’m going to give the Battle Comp an audition.
Project Featherweight with a midlength, JP LMOS carrier, CAR 3.0oz buffer and PWS FSC556 recoils like my 3gun rifle when using with 5.56mm NATO Radway Green ammo, about 15% more recoil than my 3gun rifle when using XM193 or LC M855.
A brake would help with the recoil impulse, correct. But if a H buffer smooths things out, doesn’t that mean that it is overgassed, or to be polite well-gassed? I wish there was an adjustable gas system that was adjustable as the JP, but was a bit more robust and positive in its locking at a certain gas level.
Impressive rifle for the weight when you consider a stainless 1911 is about 41oz empty!
Yes, but that’s not why I would employ a brake. Perhaps compensator would be more apropos. I want to control muzzle rise since the front end is so light.
A heavier buffer is more effective at decelerating the carrier, but does not necessarily mean the rifle is over gassed. This one may be over gassed for the weight of the JP carrier, but I do not know if this is the case yet.
When I mentioned that the rifle had a sharp recoil, this was in relative terms. It is not bothersome at all, but is a bit sharper (for lack of a better word) compared to my other three, heavier ARs. I think there are a few of variables at play here: 1. the rifle is very light (F=MA) and has less mass to react against the load. The result is a sharper perceived recoil and is the same reason my wife prefers her heavy Sig to my Glock. 2. The Colt Fiberlite stock has a smaller surface (contact) area and is unpadded. 3. The carrier is lighter as well and is probably moving faster compared to, say, an M16 carrier.
Totally agree. I had the same issue with the JP block on a 6.5 Grendel build I completed a couple of years ago. The MGI adjustable gas tube is guesswork as well.
I agree with the more durable and “beefier” bcg for reliability. Another thing that might help out with balance could be a different stock that adds a few oz of weight. I am sure you will still keep the weight at a minimum.
My wife and I took the lightweight to my uncle’s place in Idaho last week and shot a few hundred rounds of ammo, milspec and commercial (55-62 gr). It cycles well and is fun as heck, but I’ll concede and say that you might be correct re: ‘well gassed’. Now I’m aware of the brass ejection pattern debate, but brass on this one was ejecting at about 2 o’clock with commercial ammo and standard buffer after break in. Milspec damn near threw the brass in the same direction as the targets. We had another 14.5" carbine and a 16" middy that we were using with the same ammo for comparison- no issues with those. Unfortunately, were shooting so many different guns I forgot to swap in an H or H2 buffer. BTW, I do not see any odd or excessive wear on the carrier, bolt, cam pin, upper or buffer at this point (though that’s not a huge amount of rounds).
So now I’ll have to go into tuning mode and will consider some options: standard carrier, heavier buffer, XP spring, or a 14.5" middy barrel like Robb’s. I’m pretty confident the carrier will solve the issue as it then becomes a regular 16" middy, but will try to stay with the lightweight spec and employ the spring and buffers first. Additionally, rather than sending the barrel to Adco for a 1.3" chop and pin, I’m going to put together a 14.5" pencil middy upper using either the forthcoming DD or BCM barrels. I plan on swapping the lightweight carrier in that one and see how it behaves.
Oh and a BattleComp 1.0 is on the way. Even with my chunky arm grasping the end of the HG, the front end is just too light for rapid follow-up shots. As expected, my wife had a much more difficult time controlling muzzle rise than I. This is supposed to be her toy
Any other suggestions?
Thanks,
Gene
Remark: I didn’t notice as much difference as I anticipated between the lightweight and the other 16" middy we were shooting other than the lighter front end of the former. The other is about 1.5-2 lbs heavier. Of course, I wasn’t lugging a 70 lb. pack up and down the mountains beforehand either. On the other hand, both my wife and uncle were surprised as how light it is.
Before trying a heavier carrier try the LMOS JP with a BATTLE COMP or a PWS FSC556 like I did. That combo with an CAR buffer makes for a very soft shooting gun on a 14.5" midlength. A fullweight carrier with just a flash hider has much more recoil and muzzle lift.
I purchased directly from Micor. To order the Ti version, you’ll have to contact them directly. Or I can sell you a slightly used one (~250 rounds) since I’ve changed to the BattleComp 1.0:
