How do I find out which are the better parts to use for my build? Asking those with more experience is one excellent way, but how do I find experienced shooters and smiths? Unless the experience of the opinionated one is obvious, research is one way to find experience and information. You are researching if you are reading this. We all are experts in at least two fields; what we do most, and what our experience has been. I will share some information and experience about AR's, guns, gear and business, having practiced 20 years helping folks out, or limiting the consequences of, bad decisions they have made.
First, there are no free lunches. Ego, in the form of profits and greed, taint decisions of those who manufacture parts, and provide services such as gun smithing and building. Opinions are suspicious. One will urge us to use the part, a trigger in this example, that he used because he wants to be right about the decision he made on the trigger he bought and installed in his AR. That is one reason, and it is only my personal suspicion. Another reason might be the part actually is the better part. A way of knowing is to know his experience. Is the opinionated one providing information well-versed, and how well-versed is he? We notice many of the more experienced ones are not on the internet providing their opinion with glee and abundance. Because of their experience they are busy in the field of their expertise. I do not see postings of some top shooters on the world wide web. The rest of us must continue to research and discern available information.
David Tubb was working with AR rifles before AR rifles were cool which began with CNN / Gulf War I in 1992. Soon, big business marketed the civilian HMV/Hummer, AR15's with rails, but especially the .50BMG sniper rifle. We indicated interest. They, the manufacturers, responded. Tubb developed "across-the-course" big chassis AR's from then-available components, experimenting with port location, feeding and he ignored accuracy (ha). He won national titles firing the AR and its custom variants. Others such as: Zediker, Bernoski, Martin, Madesha, Tompkins, Whitley to name a few I know of off the cuff. These AR experts are a trove of experience, and they are busy working on guns and gear so they do not usually have the time to be urging others on the net to use this or that component part. But these men and women heave published material that is available to us. Also, they are available at conventions for conversation though we might mind our manners and not take up unreasonable time for our selfish desire to get what we want. Information.
Cost has soared into orbit since GWI/II because of our willingness to pay ever-increasing high prices for such "tacticool" gear, and that is not completely horrendous, I suppose. Foreigners are less-likely to invade our country if we send the aura that we are all heavily armed and able though from the clear evidence of bullet holes in the shooter tables at the local range I doubt our general high level of civilian preparedness. A soldier of Gulf War II noted the defenders of Iraq, on the road to Bagdhad, were bad marksman - no match for our training, M4's and ACOGS/EOTECKS. At the time of our invasion in GWII, we had improved our expensive gear since GWI, never mind any absence of political merit of the invasion in the first place. Powell took the hit. The rest got rich.
Be careful who's opinion you seek, use, and pass on to us. Is the information credible, incredible, and can you vouch for it? Am I getting too technical? Not in my book I'm not. This interest in guns has gotten expensive. My first precision rifle, and Remington 700 Varmint Special .308 Win cost $230.00. That was 1979. The higher, current price, is one frustrating part, and the second is the quality of the gun has decreased, in my opinion.
I prefer old the guns like the Belgium Browning A5, Colt Series 70, Gen I Winchester Model 70, Colt AR15A1 and 2, Mauser flat-bottom-knob, Garand, Remington Model 700; for some semi-custom examples, Shilen DGA, Clark Custom Bullseye 1911 actually smithed by Clark Sr, Jr., or Sam. These guns demonstrate a less-greedy, profitable, era of American gun building. The "dollar a box .22 rimfire ammunition era". That is over now. Old designs have their place, not left in the safe, but in the duck blind too. I sometimes joke to my bolt gun loving friends that bolt action rifles are WWI relics, and that they should feel more welcome in the Twenty-first century firing semi-automatic rifles. While I prefer the solid design of old guns, new designs are emerging with advances in metallurgy (titanium), and fabrics, (kevlar), and composites. AR 15's, 10's, (small chassis, large chassis) are examples of guns benefiting from technological advances.
Big chassis AR's are presently still in the experimental stage. Even AR15's continue to develop. The Lr308 bolt worked okay with moderately charged 308 Win ammunition like 40 grains of IMR 4895 or Federal Gold Medal Match 168 or 175 smk ammunition, but higher velocity loadings suffered primer blowing into the firing pin hole that was too big, .078"! Feeding is flawed.
Bullet meplat, upon entry into the chamber, ricochets off the chamber rim due to the bolt extension being too short, which often is inconsequential, and seldom effects round run-out or even disturbs cartridge over all length, hence pressure, hence degrading reliable accuracy, hence a no-go for competition, at least, and long range hunting too. The Lr308 and the AR10 bolt carrier groups use too much mass which inflicts recoil impulses that disturb our sight picture, follow-through, and follow-up, . Big chassis AR's lack adjustable gas systems that are easily and cheaply remedied; gas ports are too large, causing over-gassing, excessive reactions to the excessively-weighted bolt carrier group, and excessive burnt propellant residue in the carrier.
The firing pins on the Lr are too large. Better performing loads than those above suffer from excessive primer extrusion into the bolt face, primer piercing, jamming the firing pin and disabling the rifle. AR10's firing pin diameter dimension is correct. Triggers blow big honkers. After-market AR triggers are necessary.
Upper receivers need more metal than used in uppers that are mass-produced. Flimsy upper receivers cause change in points of impact as a marksman changes positions from prone to barricade, for example, which exerts changing forces on the forearm upper receiver, receiver junction inadequately engineered. DPMS has tried to remedy the too-heavy BCG and firing pin issue in their new GenII Lr. Our experience will know if the changes are improvements, but the upper is still flimsy, and might even be flimsier than the former model it seeks to make improve, or even make obsolete.
My experience has been what I have written in the preceding paragraph, specifically, from: first, assembling an Lr DPMS chambered in 6.5x47 Lapua using the proprietary bolt, second, a 6xc, adjustable gas block, gas port positioned forward a bit, Armalite bolt/firing pin with an Lr DPMS upper, lower, and carrier, and third, an Ar15 White Oak Armament upper build in 6RAT. I am not urging you to assemble a similar set-up. I am providing an expression of my experience with specific component parts that worked, and those that did not. The Gen I DPMS bolt/firing pin only works with short range, or girly ammo, but the Armalite seems to be the serious design in big chassis AR's because it works with big boy ammo.
Inexperience, incompetent and uncaring business management causes bad results. Experience produces reliable products. Big business bought Smith & Wesson, Colt, Remington, Winchester and the product has become something other than what it was before the buy-outs. You can decide if you like the before or after products. We do a good job asking questions on this forum. Be careful who you take advice from. There is often bias in the opinion. Remember; no free lunch.
L to R: Armalite carrier, pin, bolt, DPMS bolt, JPbolt, DPMS pin, extension,
