I hope I post this in the correct section and is technical enough to be in the tech section. This is my first tech thread, so bare with me and give me advice on what I can do better in making a tech thread.

I went out to blm land over the weekend to see what kind of groupings I can get out of my bcm 16” bfh mid length upper. The lower that it’s mated to is a ruger lower receiver with geiselle lower parts kit with a bcm trigger and vltor a5 buffer kit.

I used a Caldwell rifle rest bag to test out the groupings so as to get better grouping than if I shot without a rest. I set up a target out to 50 yards and then set it up out to 100 yards to see what kind of spread I get.

I have a vortex red dot sight mounted on my rifle and also shot with iron sights. Here’s my groupings. I also tested out my s&w m&p15 sport2 which was originally featureless. I ended up modifying it to a fixed mag since I didn’t like the finned pistol grip.

Ammo I used was federal black pack fmj .223 55grain.

Here’s my groupings.



Red dot sight at 50 yards


Iron sights at 50 yds


Red dot sight at 100 yards


Iron sights at 100 yards


And the m&p15 sport 2 iron sights at 50 and 100 yds



ETA: For my next build I plan on going with a DD 14.5” pinned and welded barrel. I’m hoping I can get tighter groups out of that than I can with my 2 current rifles.

Like most of life, repetitions is the name of the game. With that said, I feel you did better than ok. Can it be improved upon? I believe so. It's up to you. With consistent ammunition, excellent technique (for you the individual), very sound equipment; it's on you. Not familiar with the quality of your trigger assemblies but I do know a quality trigger can make a significant difference. If you goal is to minimally diminish / slow down a threat, I feel you're there now. Once I accept a particular level of accuracy from bench to unsupported, I work hard on speed and I keep that going from assorted firing psns. That's just me.

I have only one AR (20" / scoped) that I run at 100m and beyond. All others are 50m and in.

I have no issues with basic 55gr jacketed stuff at 100m. You might bump the weight up a bit and see what that gives you. And if your primary goal is for defensive or hunting purposes, you'll later want to investigate some of those rounds to include buying a couple of boxes to see how they run.

That is about what i would expect for the ammo and sighting system you used.

If you really want to know the capabilities of the guns put on an optic and get some match ammo to see what they can do.  If you are  not an experienced shooter maybe let someone else test as well

All that being said i am guessing the DD barrel will be more accurate with quality ammo.  You may get similar results with ball or it could be better, depends on the barrel

I have had barrels that shoot ball ammo 3-4 MOA and are under MOA with IMI77 grain and FGMM

I'm struck immediately by the difference between the RDS and the irons at 50 yds, and would simply offer this:

Assuming everything is tight with the RDS, I'd work on consistency of your shooting posture when using a dot (or optic of any kind).  It almost looks to me (without knowing you) that you're very conscious of good consistent technique when shooting the irons.  The target shows it.  Be that conscious when shooting your dot.  It's possible with decent ammo to shoot 2MOA with a 4 minute dot; sounds counter-intuitive to some but it's about consistency of your positioning.

Take what you're doing well with the irons and apply that to everything else.  The better your deliberate practice the better your result when you advance to executing under different types of pressure.
:)

Thanks for the feedback guys. About the ammo, originally it was intended to be used for plinking and running some drills a buddy of mine and I made up, but I decided to bring out the paper targets and check accuracy with it. I now realize that wasn’t the best ammo to use for checking accuracy with. I just wanted to see what my bcm upper can do after reading a couple of threads that made me rethink the quality of that upper. Next time I go out shooting I’ll take a box of better ammo for accuracy testing and compare. I’ll also do some shooting off the rest to see how my aim truly is. I feel that using a rest will give me an idea of what my groups should be looking like when I’m shooting off the rest.
This was my second time using the RDS. I’ve always used irons, so that might explain why I did better with irons at 50 yards. I don’t plan on using these rifles for anything more than 100 yards, I’d rather get something else much more accurate for longer distances. I’m just trying to get comfortable with these rifles and improve my accuracy and speed at close range.

From your testing with ball ammo they both prove to be combat accurate and should work well for your stated application

Just work on technique and if you want to really see accuracy potential get some good ammo to test

If you want something more accurate a reccce or spr style rifle with a SS barrel is your best bet.

White Oak makes some killer barrels for the price.  I have their SPR barrel and it is easily MOA.  Going to get the 16'' for a recce build soon

Though I appreciate the speed a red dot provides when speed counts, I always enjoy and appreciate my hard sights-only ARs. Just something about them.

Yeah, practice makes perfect, so I try and hit blm land for some shooting practice at least once a month and am planning on taking at least 2 carbine classes this year and a pistol class as well.
Hmmm, white oak. Thanks, that’s another barrel manufacturer I’ll look into. I was checking out DD and centurion.

I really like the scalar works fixed irons on my bcm upper. I’m not a big fan of pop up irons.

Looks like you are measuring from the edge of the hole. Make sure you are measuring from the center to get accurate group sizes.

Actually measure from outside edge to outside edge then subtract the bullet diameter. That is how you measure the group.

That way works too.

2 biggest things are practice and ammo.  Other factors as well.. but with irons, that's pretty decent.

Ackchually, use software to measure the mean radius so all shots count, not just the two worst.

Expect an average of 1 MOA with that arrangement.

DD and centurion are both great barrels.  They are CHF and chrome lined making them very durable.  Centurion also offers a douglas SS barrel that is more of a precision barrel

If you want more of a precision gun look into a SS barrel from White Oak, Centurion, Douglas, Rainier Ultramatch, or something form Compass Lake Engineering (Criterion, Douglas, Kreiger blanks)

If you want more of a heavy use/battle rifle with the greatest chance for good accuracy the DD and Centurion CHF barrels are top of the line.  The only other option i would throw in there if you want chrome lined is Criterion...not CHF but good profiles and chrome lined.. You can see some options HERE for Criterion

Sweet. Thanks for the input. I’m looking for something that’s durable and decent accuracy. I’m happy with the BCM, it’s also chf, and I’m not disappointed with the accuracy on it, I’m more looking to try out different manufacturers and see what I like instead of fanboying and sticking to only one manufacturer. I’ll definitely be doing some research before building the 14.5” I want as my next project.

Just out of curiosity, since you are in CA (I assume based on your location ID), what grip are you using? I was just wondering if the grip is different than you other rifles (i.e. shark fin vs hammerhead, etc.), and this difference might be also affecting your shooting?

I'm not seeing the issue. Your groups reflect the ammo used. Add in less than ideal sighting hardware for doing small groups rather than practical hits and you're getting perfectly good results. I'd honestly be amazed if you got 2" or better at 100 with that stuff and a normal barrel. Sometimes a really good barrel can make lousy ammo look decent, but that's hit or miss.

I think a lot of people cherry pick groups when they use what amounts to blasting ammo. "see, I got this great three shot group" but if they had shot the other 2 or 7 rounds it would have turned into the same size as they normally get. In my experience, Federal XM193 is some of the worst "mil-spec" ammo. I don't know if it's true, but I heard a rumor that XM193 was actually ammo that passed all the QC checks EXCEPT the accuracy. They boxed that lot up as XM instead and off it goes to people that treat mil-spec as a goal not a starting point. Like I said, no idea if that's true or not, but given the results I've personally gotten I could believe it.

If you want better results, buy better ammo. Unfortunately, that is likely to cost more. I am ragging on Federal, but even the best M193 isn't exactly precision ammo. Folks suggested some options and I'll probably try a few myself, but I reload even my plinking ammo these days, the M193 is just part of the ammo fort.

Im using a magpul grips on my rifles. I have fixed magazine configurations on them because I can’t do the fingrip thing.

My next range day I plan on bringing some good ammo. I’m not quite sure yet what ammo I’ll bring, it all depends on what I can find at the local gun stores around me. I’m happy with these results considering the posts I’ve read about BCM barrels not being good quality barrels that lack accuracy. With better ammo I’ll see what it can do at 50 yards and 100 yards again and compare the results.
For my next build I want to try a different barrel, so I’m either going with a 14.5” centurion or dd barrel pinned and welded. I want to see for myself what difference the barrel can make.

BCM makes very few precision oriented barrels, despite any marketing that may talk about accuracy. It's not really their niche. Check out Noveske and LaRue if you want easy but accurate. Order, install, enjoy.

ETA: not a slam on BCM, their focus for barrels is effective accuracy for the intended role. Then it comes down to life span, reliability, profile... If your intended customer shoots standard mil-spec ammo, putting a ton of work into a barrel's precision is a waste of resources. Good enough is good enough, put the effort elsewhere.

If you can, bring a few different types of ammo.  Maybe some better 55's, some 69 smk, some 77 OTm, etc.  I only say this because every barrel has its own likes and dislikes.  You may bring one "match" type ammo and your barrel doesn't like it, then you walk away worse than you started the day.  Just a suggestion.

I think for what I use it for, it’s fine. I pretty much just use it for plinking and running drills. If I need it for home defense I know it won’t fail me.

Good idea. I’ll bring different types of ammo on my next range day to see what shoots better out of this rifle. Thanks for the suggestion.

Not bad for bulk ammo and a red dot......match armmo and a scope with decent magnification will tighten those groups up