More AR Questions, Uppers, Twist Rates and BCGs

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sigcurious

New member
I intend to assemble an AR(will be my first!) for general range use and plinking, and have the following questions.

Uppers Assemblies: BCM vs PSA vs Spike's, for my stated use and experience level, are there any appreciable differences?

Twist Rates: 1/7 vs 1/8 from what I could find in searches, for the above listed use either should be good to go. Are there any reasons to go with one or the other?

BCG: Auto vs Semi(also BCM vs PSA vs Spike's), again from searches I couldn't find appreciable differences for the casual user. Any reasons to get one or the other? Also would it be a good idea to match the manufacturer of the BCG and Upper or would mix and match be ok?

My guess is that for all the questions the answer is roughly the same, whatever floats my boat will work just fine. But I wanted to put it out there to see if there's anything I'm missing information wise from only having a basic understanding of the information I've been looking at.
 
Twist Rates: 1/7 vs 1/8 from what I could find in searches, for the above listed use either should be good to go. Are there any reasons to go with one or the other?
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With either of the two you can go from 50 to 80 gr bullets. The inverse isnt true, meaning you can shoot light bullets in a fast twist, but you can't shoot heavy bullets in a slow twist.

I like the 1:7 because I do shoot my AR at 1000 yard matches, I want to be able to go to the heavier 90 grn pills. With the 1:8 you're limited (on the heavy side) to 77 and 80 grn bullets.

This chart shows the results of light and heavy bullets in a fast and slow twist barrel.

Twist%20compairson.jpg
 
The M16 BCG slows the action cycle, and aid in reducing the felt recoil pulse. Coupling a M16 BCG with a H2 buffer and a heavier spring will be the optimal setup, and will help control muzzle-flip (and recoil pulse).

The ROT on the barrel determines how heavy (or long) a bullet you can use. The slower the twist, the lighter the bullet can be while still maintaining accuracy and consistency. The faster the twist, the heavier the bullet can be. Generally speaking:

1:9 = 45-62gr
1:8 = 50-85gr
1:7 = 55-90gr

Keep in mind that you can certainly use cartridges that are outside the ranges listed above, but your accuracy will suffer.
 
Uppers Assemblies: BCM vs PSA vs Spike's, for my stated use and experience level, are there any appreciable differences?
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Not especially. They're all good quality. I tend to go for BCM, but the others have quite a few fans too.

Twist Rates: 1/7 vs 1/8 from what I could find in searches, for the above listed use either should be good to go. Are there any reasons to go with one or the other?
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If you're sticking to the 55gr (M193) and 62gr (M855) types of loads, both will work just fine. As Kraig pointed out, it's only going to matter if you go with the really heavy bullets.

BCG: Auto vs Semi(also BCM vs PSA vs Spike's), again from searches I couldn't find appreciable differences for the casual user. Any reasons to get one or the other? Also would it be a good idea to match the manufacturer of the BCG and Upper or would mix and match be ok?
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The only difference between semi and auto bolt carriers is some extra metal at the bottom rear of the carrier. Some prefer the auto carriers for that- the extra weight is seen as a boon when it comes to smooth functioning. IMO, it doesn't matter. Most of my rifles have semi carriers, one has a full. I have some spare BCGs that are full. I haven't swapped out the semis.

As for manufacturer, my view is that as long as you're buying a bolt that's 158 Carpenter steel and HP/MPI tested, you're good. IIRC, all three companies do that and stake the keys well. You don't need to worry about mixing and matching, but I'd probably just get them at the same place you get the upper... fewer shipping charges.

My guess is that for all the questions the answer is roughly the same, whatever floats my boat will work just fine. But I wanted to put it out there to see if there's anything I'm missing information wise from only having a basic understanding of the information I've been looking at.
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Whenever you're dealing with quality makers (and by all reports, BCM, PSA, and Spike's are quality... I've yet to regret any of the parts I've bought from BCM or Spike's), it's all personal preference. The AR world can be very much a "flavor of the month" thing; when I got into them, it was all about BCM, then Spike's, and now it's all about Palmetto State Armory. I still tend to go BCM (or Spike's when I can't get BCM), but any of the three will serve you very well.
 
Thanks for the input guys! Any suggestions on where to price BCM stuff aside from their own website? Right now my choice between the three is based mostly on what I foresee being available in a few weeks when I start buying parts.

Also, any suggestions on handguards that have either just a top rail or a bottom and top rail? The quadrails look uncomfortable and I don't intend to mount a million gadgets, maybe just a front mbus sight when I get an optic to replace the regular FSP and a foregrip if I the mood strikes me.
 
Any suggestions on where to price BCM stuff aside from their own website?
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That's where you get it. You can buy it elsewhere, but you aren't saving any money (at least, that I'm aware of). The best way to do it is find what you want and select the "Email me when back in stock" option. Then when you get the email, you jump on it RIGHT NOW. Some stuff goes pretty quick.

Also, any suggestions on handguards that have either just a top rail or a bottom and top rail? The quadrails look uncomfortable and I don't intend to mount a million gadgets, maybe just a front mbus sight when I get an optic to replace the regular FSP and a foregrip if I the mood strikes me.
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Depending on the optic, there's no need to remove the FSB (it doesn't present an issue when using a CQB optic like Aimpoint or EOTech, and for magnification of 3x and over it disappears anyway). If you are thinking about removing it anyway, do yourself a favor and just buy a setup with the handguard you want from the get-go. The nicer rail systems with an ovoid profile (Daniel Defense, LaRue) aren't too bad-you just get rail covers for the areas you will leave unused.

Otherwise, it's mostly a matter of preference; I've used the Troy TRX Extreme handguard on one rifle and it's not bad- you just add rail sections where you want them. However, removing that FSB is not a very simple task and some of the aftermarket gas blocks really don't like to stay put (there might be two piece no-smithing unrailed handguards out there, but I've not seen them... the Daniel Defense Omega rail is a fantastic drop-in free float 4 rail model though). I'd decide if you really want a new rail system or not, and exactly what kind of thing you'd like to end up with and try to get that from the start.
 
I just dealt with Delta3tactical.com. They had most the stuff I wanted from from different places all on one site, and some things cheaper. I got an upper and lower, bcg, charging handle...etc. Got a handful of free magpul followers too.

I kinda wish I'd bought a complete upper. Probably would have cost the same as what I'm putting together anyway. Superior barrels have some set ups that are gauronteed MOA and grouped at 500m
 
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BCM>spikes=PSA

BCM is proven and has excellent customer service. I dont think ar-15's are really "flavor of the month" aside from when it comes to casual shooters. And typically, that revolves around whatever looks the coolest or is cheapest.

You always hear the same few names when you ask about high end ar's and they dont include spikes or PSA.
 
I've been looking at those 3 mostly because they all seem to get good reviews, and they all have parts that fit into the price range I'd like to stay in.(aside from some of the high end BCM stuff, not looking to spend that much for my first hehe)

That being said, I'm open to other options, particularly for the uppers. $800 would be the high end of what I'd like to spend including the BCG for the upper. So if there are some other companies I should check into please let me know, as I'm new to the AR world and there seems to be more people making ARs than you can shake a stick at.
 
Speaking from experience, get a BCM and don't look back. Good products and good customer service, an unbeatable combo. There is a reason a lot of their products are on backorder, their uppers get snagged up with an insane quickness.

Also, you asked for a high-quality handguard without the continuous rail...

http://www.bravocompanyusa.com/BCM-...eceiver-Group-p/bcm-urg-mid-16 bfh vtrx13.htm

That sound you're hearing is two birds getting hit by one stone. :D
 
I was looking at that upper, it's a little more than I'd like to spend, but certainly an option. Now that I realize they make covers for rails it opened up the options a bit.
 
On the topic of twist rates, keep in mind that while the faster twist such as 1:7 will stabilize a longer (heavier) bullet, it also has the potential of disintegrating the really lightweight varmint style bullets. The fast twist literally can spin the jacket right off of them.
If you're planning on reloading and shooting long range, go 1:7 or 1:8. If you plan on simply plinking cheap/surplus ammo and possibly shooting light varmint bullets, you might want to consider the 1:9 or slower.

+1 on BCM being good stuff. I sourced BCM for a few parts of my AR build (my first AR as well) and I am very pleased with the quality, price and service.
 
My 5.56 AR is a RRA Lar15 with the national match trigger. I prefer the 1 in 9 twist in a 16" barrel. I then purchased a Stag 7 upper in 6.8 SPCII with a 1 in 11 in twist on a 20" tube.It fits like a glove. The set ups work exceptionally well fo me both at the range and in the field. The 1 in 9 twist for my 5.56 allows for a wide range of bullet weights. When coyote hunting I simply switch my upper to the 6.8 SPC and run with a 110 grain BTHP. Drops em like a box of rocks.
 
One of the RRA uppers in the hunter series (ATH, Coyote and?) are excellent guns.

More for target or yotes than tactical with the 18 inch barrel or longer in some cases (stainless). 1-8 twist with Wylde chamber. I have shot 1-9 and those can go to the 68 gr with fine accuracy though its pushing it a bit far and 77s probably need the 1-8 to be sure.

I like the ATH a lot.

Chromed BCG, chromed two stage match trigger than takes you up to anything short of Camp Perry IMNSHO (not so humble opinions!)
 
I haven't looked at the RRA stuff, I'll have to give it a look. At this point reliability from the parts I combine is paramount, accuracy is second. I'm not a great shooter(yet! :D), and my intended use is more would require "minute of fun" accuracy. That being said, if I end up with a fairly accurate rifle that I can grow into, I would not be upset at all hehe.
 
You can get a Spike's BCG from aimsurplus.com for $110 shipped. I don't see any reason to spend an extra $40 just because it says "BCM" on the side.

Mixing components is perfectly fine. These companies don't manufacture their own parts, they assemble them. Many of these companies get their parts from the same places. As long as said parts are in spec, they will all work together.

I have a barrel from PSA manufactured by FN, upper receiver made by Aero Precision, BCG from Spike's and a charging handle from BCM.

As far as rails go, I have a 13in Troy TRX Alpha battle rail. It's the lightest weight rail I've held. It has a very small diameter, which makes it comfortable to hold. It comes with 3 rail sections that you can place where ever there's a hole. I also see no point of a quad rail. It adds unneeded cost and weight.
 
I agree with the guy that suggested a 1-9 twist barrel. It's pretty much the ideal, except for special applications - heavy bullets for the 600 yard line in service rifle matches, and for stabilizing 62 grain tracer bullets. (To get enough tracer compound in a 62 grain 22 caliber bullet, they had to make it thicker through the body with less pointyness. That's why military barrels are 7-twist.)

A 7-twist barrel actually over-stabilizes 55 grain bullets. Part of the effectiveness of the high velocity little bullet is its propensity to tumble and fragment in tissue. If you overstabilize it, it only drills a clean little hole and exits the other side - tends to make the other guy very annoyed. 9-twist is probably better for the civilian.

Keep in mind that, despite the plethora of brands, you can probably count the companies that actually MAKE the parts on one hand. And they are all pretty well screwed together the same way. So unless you are going for something off the beaten path, like a monolithic upper or a piston conversion, it really doesn't make any difference what animal, bug, or mythical beast is engraved on the magazine well - it's probably hard to buy a bad Ar15.

But that's a good thing, because right now you may have a hard time buying ANY Ar15. Most vendors are short of important components such as barrels in popular lengths, and have long waiting lists. A few have actually suspended taking new orders until they work their way through the backlog.

I ordered a new 20" flat top rifle kit on March 7. I bought it from J&T Distributing in Winchester KY because at that time they were the only reasonably priced vendor taking order for 20" rifle kits. My kit shipped yesterday, but only because I adjusted the order to include a chrome-lined barrel at a $50 upcharge, otherwise they didn't have a guess how long I'd be waiting. (Nothing against J&T, by the way, except that they are in Kentucky, as am I, which means they have to tack 6% Kentucky sales tax on my order.)

You may want to check your local retailers, and see what, if anything, they have on the rack.
 
I had looked at aimsurplus for stuff, but most of the things I have been looking at are sold out. In a couple of weeks, it will mostly come down to who has what in stock. Spike's and BCM's direct prices are a little more than some of the others but if they have the parts in stock when I start ordering that's who I'll go with. I'll definitely check back with aim before ordering as I was intending to get either a BCM or Spike's BCG since I was going to order other parts from both of them anyway.

As to barrel twist, I don't intend on putting holes in people, nor would my soon to be AR be a goto HD gun, so remaining stable on impact is not a concern for me.
 
None of the companies you mention are necessarily manufacturers. BCM uses ER Shaw barrels, PSA uses FN barrels, not sure about Spikes, Most all of them either buy finished upper and lower recievers from another company such as Aero Precision or they buy the rough castings direct from the forging company and do the final finish machining themselves. BCM makes great products, they are very dedicated to what they do. PSA uses very good parts usually at a much better pirce. If I were getting ready to build another AR style rife, I would go with whichever has the best price at the time. I have one that I built using PSA receivers and an ER Shaw stainless barrel, I bought my bolt carrier from BCM and the bolt itself is Stag. It has functioned flawlessly from the very beginning and I have about $750.00 in it not counting the optics.
 
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