Building an AR-15

[SSN Vet]

I've gotten my personal best groups (with iron sights) from my Delton middy build with a 1:9 16" barrel and my hand loads with 69 gr. Sierra Match Kings.

What is your purpose for the rifle?

If for fun and self defence, I don't know why you would feel the need to shoot the heavies.

Barrier penetration? Super long range?

IMHO, neither of these have much to do with fun and self defence. And as noted, you won't be getting the velocity needed for long range shots with 75 gr+ ammo. from a 16" barrel.

Things I've learned since my build...
1. If you take reasonable care of you rifle, a chrome lined barrel isn't necessary and imo. isn't worth the extra $50 it cost me.
2. HBARs make ARs front heavy.

 

[Bartholomew Roberts]

If for fun and self defence, I don't know why you would feel the need to shoot the heavies.

Until recently, the most effective self-defense ammo for .223/5.56mm has been the heavy stuff (75gr+). Although if the new 62gr SOST gets into civilian hands, that may no longer be the case.

And as noted, you won't be getting the velocity needed for long range shots with 75 gr+ ammo. from a 16" barrel.

According to my ballistics calculator, M855 at 2,950fps muzzle velocity will have 30.7" of drift at 500yds in a 90 degree 10mph crosswind.

By comparison, the 75gr Hornady at 2,550fps muzzle velocity will have only 28.7" of drift at 500yds in a 90 degree 10mph crosswind.

The 75gr will have about 15" more drop at 500yds (being heavier and starting out slower); but drop is really the easy part of shooting past 300yds (as long as you can estimate range well). The hard part is doping the wind.

Either way, the 75gr is plenty capable out of a 16" barrel. It goes transsonic around 850yds. 55gr M193 out of a 16" barrel goes transsonic at about 575yds. And M855 starting out at 2,950fps goes transsonic at around 750yds.

Personally, I don't like 1:9 because my last 1:9 wouldn't shoot the heavier match ammo. I do not like a barrel that puts Black Hills match ammo into 4-5" groups at 100yds. My current 1:8 and 1:7 barrels put ALL my match ammo into nice tiny groups, whether it is 52gr Sierra or 77gr Mk262. For that reason alone, I favor the faster twists.

 

[Zerodefect]

And I do believe SSA ammo has even better #'s.

The chrome is a nessesity in AR's. People have died to learn from this mistake. As for m4 feed ramps, take a look at one sometime. You can clearly see where the rounds were dragging on that m4 ramp. So the needed for full auto only bit is BS.

1/7 is better for all the heavy 62-75gn ammo. Which is proving to be better for defense.

So it real boils down to whether your AR is for serious business, or if its a play toy.

 

[kwelz]

So it real boils down to whether your AR is for serious business, or if its a play toy.

I think this sums up all the arguments on this board and others pretty well.

 

[ol' scratch]

I built my first lower at the kitchen table using needle-nosed pliers, a tack hammer, a razor knife (to push down the detents) and an adjustable wrench. It has worked out very well.

The second AR lower I built I had a garage so I used it. I upgraded my tools to include a Black and Decker vise bench. That has worked out well too.

You don't need many tools to build the lowers. I always hear people say there are things that would be 'nice to have.' If you are going to build more than one, or you want to build an upper, the tools are a good investment.

 

[gondorian]

It is easy to find carry handles cheaper that $75, see here and other places, so I would ditch the carry handle and just save the money for optics. Definitely get the M4 feed ramps.

 

[PandaBearBG]

I thought that not all carry handles from different manufacturer's have slightly different slightly different heights, which could effect height adjustments? I'm guessing that the major manufacturer's probably are correct heights but some off brands are a bit off? Is this true? That has always been the reason I have been hesitant about getting a Detachable Carry Handle. Or maybe I'm just misinformed.

 

[RP88]

A few questions-

What tools will I need to assemble the lower? I really don't have many tools in general let alone gunsmithing tools.

I have assembled two lowers. I used a couple pieces from my AK-47 cleaning kit (the buttstock pods that come with the gun), a small hammer, a leatherman multi-tool, a piece of paper, and small needle-nosed pliers.

The main tools you'll need are a small hammer, needle-nosed pliers, a piece of paper, and some hole punches/drift punches. Given my layout, you can guess what I substituted with what.

Assembling a lower is not hard, and I used youtube for the instructions. Just make sure to do it in a well-lit, clean area in case you accidentally let a spring fly across the room. Those things get lost easily. You don't need any fancy gunsmith specialist tools or anything. You can probably assemble one with chop sticks, two fingers, and your forehead if you're resourceful enough.

Any word on Del-Ton? I've read some of the reviews and they all seemed really positive.

I had a middie, but sold it to fund a safe and a Glock after i built my second AR; just didn't need the Del-Ton after the second one. It worked fine with everything, though - from wolf to PMC to UMC. Just don't do what I did and use crappy mags. get you some good ol' GIs with magpul/no-tilt followers. I had quite a few jams that were only due to mags. No gun-related problems.

Accuracy was good, especially because I got the heavy barrel. It shot as almost good as my current AR. Quality and fit/finish were like every other AR I've handled.

The only downside is that I'm pretty sure that the main parts are batch tested, and that the carrier is not staked, and the bolt is your run-of-the-mill blue-insert bolt. Definitely miles away from a milspec gun. if I were you, I'd simply select "none" for the bolt and carrier option, and take the money saved and put it towards a milspec bolt carrier group.

- Chrome lined barrel ($45) Should I get the 1x7 or 1x9 twist? most my shooting will be within 100 yards with plinking ammo, though I may reload some if I get a turret Press.

- Detachable Carry handle ($75) Some day I would like to put optics on this, thats why I'm getting the flat top.

- Flat Top Upper with M4 Feed Ramps ($25)

definitely get 1x7 twist, so you can shoot whatever you want through it. I'm not sure if the M4 feed ramps are done properly or not. If they aren't cut like they're supposed to, then I'd pass on that and just save your $25. I'd also not get the detachable carry handle until you've shopped around. You can find military surplus ones laying around for half that price if you look hard enough - at least less than $75...

Any recommendations for other upgrades from Del-Ton? I'd like to keep the price low but am open to any suggestions.

as said: better bolt carrier group. one from BCM, LMT, etc. come to mind.

You'll like the rifle once you get it running. I surely liked mine, and wouldn't mind getting a 20" from them in the future.

 

[gdcpony]

mssshootnit's assertions are far from reasonable or even realistic. 1/12 did not stabilize the 55 grain bullet well. In fact that was the whole point. A short bullet out of a 1/12 would tumble if hit by a light breeze. Keyholing was an issue to say the least.

1/9 is impractical for the longer/heavier bullets common for long range or self defense shooting. It under-stabilizes the round which can cause accuracy problems.

1/7 on the other hand gives you the largest range of available ammo. The only thing it isn't useful with are very light Varmint grenades, which should not be shot out of a carbine AR anyway. Those belong in a longer range weapon. Any round 50 Grains and up should be just fine. I have seen 45s used reliably but don't see a reason for them. Anything less than that will be over-stabilized. This won't affect accuracy like some claim but it will spin the rounds apart.

Finally there is no real difference in barrel life between the 1/7 and the 1/9. Chrome lining is what will show the real difference there.

M4 Feedramps have shown to have a very big impact ont he reliability of the AR platform, once again especially with heavier bullets.
Look at a AR with standard feedramps that has been ran hard. You will see marks right about here the BE meets the receiver. These are caused by the bullets impacting a bit lower and this can lead to issues.

As a .223 fan I feel the need to reply to this. I love the round as it is meant to be used and in about any platform too. I have owned bolt guns, break actions, and some AR's and have loaded my own ammo for them.

1:12 is what I have seen most often in my non-AR .223's. Many of them would put the average AR to shame as far as precision. Not a bash just a plain fact. My Howa blasted .5" groups with 55gr ammo all day long. With handloads it would go .375" inch when rested well and I did my part. It would do this with 40gr pills as well. I have shot some pretty stupid ranges to see what would happen and can tell you I never had a 55gr bullet key hole out of any .223 regardless of twist.

At the same time my Bushmaster with its 1:7 twist was notorious for not getting the lighter bullets to target. They just flew apart once velocities broke about 3500fps. That said, it was beautifully accurate -.75"- with a load of A2230 behind a 55gr bullet.

The 1:9 is a good compromise rate. In a carbine the bullet will not generate enough velocity to destroy the lighter slugs. They will be plenty of stability for most any bullet the AVERAGE shooter will need. Will it control the super heavy weights? No. But how often are you likely to NEED them? I have yet to in two decades with this round.

As far as light weight bullets belonging in a "long range weapon" I don't see it. Granted 40gr polymer tipped bullets did do very well for me on a number of occasions, but I would not count on them in a high wind beyond 300yds, maybe less. Heavier slugs are made for that work. That is on of the main reasons they exist. A 75gr bullet will do what it is meant to do (or not do) and that is drift. You might have to dial in a few more clicks of elevation, but it will buck the wind and stay more on course than anything lighter.

Now for the heavier bullet for defense theory. Go hunting yotes. They or a SMALL deer have about the same "resistance" (better word anyone?) to a bullet impact as a human body. From experience I can let you know what you don't want. A heavy bullet passing straight through venting little of its energy on the target. In hunting it means the animal runs farther before (if) it dies. Shot placement matters more, and over-penetration from the bullet retaining so much of its energy can cause problems down range. I doubt my neighbor would like bullets flying through his walls regardless of the reason and he has kids. If your assailant is wearing body armor then you might need it, but I don't see that as a "likely" threat. I know someone will start listing heavy bullets meant to make the .223 a big game killer, but they still are over kill on a human.

For defense, I like what I hunt with. A frangible bullet that transfers as much of its energy as possible. When I gut a 'yote to see the damage, it looks like someone turned on a blender inside the ribcage. That is what a person would look like (thankfully never had to prove it in practice). They are not going to function very well with nothing intact beneath their throat.

After ranting like this, I would like to add a couple disclaimers. If you plan to shoot any form of long range competition then the 1:7 WILL be the better bet. I am working on the assumption that you are like 99.8% of .223 shooters who will enjoy the round for plinking (55gr dominates here), varmint hunting (50gr and less here), or just to have for the "just in case" of it (no one really will care then).

Just my opinion on the round.

 

[HKGuns]

Or if you are using longer OAL rounds (heavy 75gr+ ammo again) or softpoint hunting rounds without a cannelure on the bullet. These also benefit from M4 feed ramps for obvious reasons. Another plus is that if you use mags until they fail, you'll see marginally longer lifespan with M4 feedramps because the weaker springs will continue to feed with M4 ramps when they will cause a stoppage with the standard ramps. However, given the cost of magazines these days and the normal useful life of one, you are probably better off just buying a new mag.

Good catch and thanks for clearing that up BR. You learn something new every day. This is turning into an information filled thread.

 

[HKGuns]

As a .223 fan I feel the need to reply to this. I love the round as it is meant to be used and in about any platform too. I have owned bolt guns, break actions, and some AR's and have loaded my own ammo for them.

1:12 is what I have seen most often in my non-AR .223's. Many of them would put the average AR to shame as far as precision. Not a bash just a plain fact. My Howa blasted .5" groups with 55gr ammo all day long. With handloads it would go .375" inch when rested well and I did my part. It would do this with 40gr pills as well. I have shot some pretty stupid ranges to see what would happen and can tell you I never had a 55gr bullet key hole out of any .223 regardless of twist.

At the same time my Bushmaster with its 1:7 twist was notorious for not getting the lighter bullets to target. They just flew apart once velocities broke about 3500fps. That said, it was beautifully accurate -.75"- with a load of A2230 behind a 55gr bullet.

The 1:9 is a good compromise rate. In a carbine the bullet will not generate enough velocity to destroy the lighter slugs. They will be plenty of stability for most any bullet the AVERAGE shooter will need. Will it control the super heavy weights? No. But how often are you likely to NEED them? I have yet to in two decades with this round.

As far as light weight bullets belonging in a "long range weapon" I don't see it. Granted 40gr polymer tipped bullets did do very well for me on a number of occasions, but I would not count on them in a high wind beyond 300yds, maybe less. Heavier slugs are made for that work. That is on of the main reasons they exist. A 75gr bullet will do what it is meant to do (or not do) and that is drift. You might have to dial in a few more clicks of elevation, but it will buck the wind and stay more on course than anything lighter.

Now for the heavier bullet for defense theory. Go hunting yotes. They or a SMALL deer have about the same "resistance" (better word anyone?) to a bullet impact. From experience I can let you know what you don't want. A heavy bullet passing straight through venting little of its energy on the target. In hunting it means the animal runs farther before (if) it dies. Shot placement matters more, and over-penetration from the bullet retaining so much of its energy can cause problems down range. I doubt my neighbor would like bullets flying through his walls regardless of the reason and he has kids. If your assailant is wearing body armor then you might need it, but I don't see that as a "likely" threat. I know someone will start listing heavy bullets meant to make the .223 a big game killer, but they still are over kill on a human.

For defense, I like what I hunt with. A frangible bullet that transfers as much of its energy as possible. When I gut a 'yote to see the damage, it looks like someone turned on a blender inside the ribcage. That is what a person would look like (thankfully never had to prove it in practice). They are not going to function very well with nothing intact beneath their throat.

After ranting like this, I would like to add a couple disclaimers. If you plan to shoot any form of long range competition then the 1:7 WILL be the better bet. I am working on the assumption that you are like 99.8% of .223 shooters who will enjoy the round for plinking (55gr dominates here), varmint hunting (50gr and less here), or just to have for the "just in case" of it (no one really will care then).

Just my opinion on the round.

Thank-you for sharing your experience, great post.

 

[mshootnit]

The only ammo that the 1/7 twist barrel benefits is too heavy for the platform. The rounds start out at about 2550 fps (too slow). To put it in perspective this is about the speed of a 30-30 but with bullets at about half the mass. Sounds like a winner to me! What you have is a carbine craze with people who refuse to see the limitations of the platform. The ideal AR or M16 is the 20" A3 with a 1/9 twist. Shoot ammo up to 69 grains and rest assured you are whooping ass on everything else. Period. Just ask the last coyote I took out at 236 yards with a 62 grain partition. Oh wait... that was a 1/12 barrel. Guess maybe it was fluke!

 

[Bartholomew Roberts]

The ideal AR or M16 is the 20" A3 with a 1/9 twist. Shoot ammo up to 69 grains and rest assured you are whooping ass on everything else. Period.

I can shoot 55gr FMJ, 62gr FMJ, 62gr Partitions and 45gr WWB JHPs out of a 1:7 with practical accuracy that is the same as any 1:9 barrel. I can also shoot 73gr Berger, 70gr TSX, 75gr Hornady (AMAX or BTHP), 77gr Sierra.

However the reverse is not always true. 1:9 produces marginal stability in the heavier rounds and some 1:9s will handle them and some won't. And what do I gain for the tradeoff? Minute degrees of improved accuracy in 55gr ammo (which typically isn't purchased for accuracy purposes to begin with) and the ability to use thin-jacketed varmint rounds of less than 45gr pushing 3,500fps?

For my intended uses, that isn't a good trade-off. I don't know if it suits the original poster's uses or not; but I think we would provide a lot more useful information to him and other posters by giving as much hard data as possible instead of assuming that he will use his rifle like I use mine and giving him my opinion about what works best for me.

The rounds start out at about 2550 fps (too slow). To put it in perspective this is about the speed of a 30-30 but with bullets at about half the mass. Sounds like a winner to me!

Actually it does do pretty well. 12" penetration with upset after 0.5", a maximum cavity of 5.5" wide occuring at 5.25" depth. Of course, that is the Hornady defense stuff which is loaded about 25-50fps hotter than the Black Hills Blue Box I used...

Also not sure where you got your numbers; but the Hornady Leverevolution in .30-30 out of a 20" barrel only hit 2216fps in this gel test. Although you'll note that the 75gr TAP compares pretty well to it despite being less than half the mass and only about 400fps faster.

 

[taliv]

i don't care for 1/9 at all.

i'd take a 1/14 and shoot it with 55g bullets only
or a 1/7

i'm trying to remember if i still have any ARs that are NOT 1/7. I think I got rid of all of them.

The only ammo that the 1/7 twist barrel benefits is too heavy for the platform

that's just silly

 

[HKGuns]

that's just silly

Silly? You can't even load them into magazines! How is that silly?

COL for the 55 grain AR load is usually around 2.25 give or take and they just barely make it into my Pmags @ 2.24+/- .01.

Look at the COL for an 80 grain there is no way they'd fit into an AR magazine. 75 & 77 might just make it but it would be extremely close and I don't know I'd trust them to extract correctly.

Here's a picture of a 55 grain Sierra Spitzer COL measured at 2.245 as you can see they barely fit the magazine. I'd have to say it isn't exactly silly if your bullets don't fit your magazine.



I've never loaded those big ones so I suppose there may be a load out there that will allow them to fit into a magazine, however, I'd be curious if an off the shelf bullet would fit and chamber reliably from a magazine.

 

[taliv]

77g SMK, 75g hornadys and others are easily loaded to magazine length. In fact, I have 100g bullets that are pretty dang awesome that load to magazine length.

The only bullets I have that can't fit in a pmag are my 80g SMK, but I only use those in competition and NRA rules state you can only load one round at a time anyway, so there's really no need to seat them to magazine length.

why wouldn't you trust 75/77g to extract correctly? what does extraction have to do with this conversation?


(btw, there are military loads using both the 77 and 75g bullets. they clearly wouldn't have much use for them if they wouldn't fit in standard magazines)

 

[HKGuns]

Yeah, I figured there were loads out there that would be seated deep enough to fit for those rounds. I'd like to see the 100grain load that enables you to seat it deep enough.

Feeding reliably comes into play if they're marginally able to fit into the magazine properly.

Edited to add....not trying to start a fight with you in any way......I'm going to crack open my loading manuals and look for 80 & 100 grain loads that fit. Do you know the max COL that will fit in a standard magazine? It appears to me it would be right around 2.25.

Given a 1/9 will shoot up to 73 grains with enough spin in general, then 75 & 77 are really the only two that you can't use with the 1/9 and reasonably expect to use a magazine.

 

[taliv]

 

[mshootnit]

30-30 150 gr. HP 2390 fps factory load.
75 gr. Hornady 2590 fps 16 in 1/7 barrel, phantom flash hider.
When you calculate the number of factory loads that suffer in accuracy due to the 1/7 twist, then compare that to the number of factory loads that require a 1/7, the choice is quite clear to me. By traditional standards 1/7 twist is "radical" and in the sporting world is "unnecessary" except for long range target shooting which does not involve carbines.

 

[mshootnit]

I could be wrong... I was once...
Just one man's opinion.

 

[Bartholomew Roberts]

When you calculate the number of factory loads that suffer in accuracy due to the 1/7 twist, then compare that to the number of factory loads that require a 1/7, the choice is quite clear to me.

OK, well we have seen that 10 55gr BlitzKings will go into 0.76" at 100yds from a 1:7 Noveske barrel. If that is suffering in accuracy, then I can live with that kind of suffering.

On the other hand, my own personal Bushmaster 1:9 would put Black Hills Mk262 into 4-5" 5-shot groups at 100yds. Now that to me is unacceptable; because I do use and do want to use those heavier loads. So from my perspective, losing a few fractions of an inch accuracy-wise on the 55gr and lighter loads is more than worth the cost of being able to shoot the heavier stuff sub-MOA.

Of course all of this ignores the fact that a 1:7 or 1:9 chrome-lined Delton firing cheap 55gr ball isn't going to be producing the kind of groups where you'll notice any difference in any case.

 

[Wildyams]

well, i went to my local store to pick up my lower, but they were out of stock.

so now I need to wait for them to get more in, or I could have them special order me one.

is there a big difference between the different brands of lowers?

i know there two different kinds, I think they are cast and milled? and I've heard the milled ones are better quality for the most part.

 

[taliv]

there are old cast ones and you definitely don't want those

there are forged, which are also milled a bit. these are high quality and cheap. colt 6920 is a forged lower.

then there are lowers completely machined from a billet of aluminum. tend to be expensive and serve niche markets

 

[KAC1911]

Not one mention of a 1:8 twist. Isn't that a compromise between the two?

 

[HKGuns]

AR15.com "Library" on Twists

http://www.ar15.com/forums/topic.html?b=12&f=6&t=102