What's a good bullet weight and cartridge for my Colt 6920?

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[ARCHIVED THREAD] - What's a good bullet weight and cartridge for my Colt 6920?

Posted: 5/23/2005 4:18:18 PM EDT

I'm currently shooting 55 grain Remington UMC cartridges. I'd like to try something different. (and I don't want to reload.)

What's the heaviest bullet I can try that will still shoot fairly accurate at 50 to 100 yards as the UMC stuff. Hopefully I can find something in the bullet weight you recommend at Gander Mountain real cheap. Since I'm using the rifle for informal defense type shooting, and not serious target or dog shooting, I prefer not to be shooting the expensive name brand stuff at $10+ box

Posted: 5/23/2005 4:33:34 PM EDT

[#1]

I think you have a good question here. I think all ar15 shooters have to think this one over. The only real answer is going to be to shoot a few types to see what works.

From my experience I can mention this:

I have a 1x7 colt 20" upper with one of the old 3x colt carry handle scopes. This gun shoots 55 grn fmj ball better than Black Hills 77 grn match? go figure.

My DPMS M4 with 1x9 stainless 14.5 bbl. shoots 55 grn Winchester -Nosler Ballistic tips at about 2-3 inch groups with an ACOG on board. Also does not like the 77 grn stuff.

Good luck in your selection. Maybe some guys with the Colt 6920 can comment on what is working for them.

Posted: 5/23/2005 4:50:03 PM EDT

[#2]

Quoted:
I have a 1x7 colt 20" upper with one of the old 3x colt carry handle scopes. This gun shoots 55 grn fmj ball better than Black Hills 77 grn match? go figure.

At what distance? There has been some conjecture that you don't see the true potential of the heavier loads until you are shooting at or past 200 yds. I shoot 77gr SMK reloads out of everything I own. One of them has a 6920 barrel on it and it shoots them very well. Another is a chopped 20" Colt barrel, chopped down to 16.25" and it shoots the 77gr loads very well also out to 100 yds. It varies, as you can tell.

If you want cheap, reliable loads, stick with what you have, the 55gr factory loads, other than Wolf. Wolf is ultracheap and fine for blasting ammo, but I would never bet my life on it.

Posted: 5/23/2005 4:50:08 PM EDT

[#3]

If I was on a fixed income, I'd use 62 Grain Wolf. It's dirty and tends to jam...but I've had some nice groupings with it.

ETA.
Gun shows are a great source for good, cheap ammo.

Posted: 5/23/2005 5:53:28 PM EDT

[#4]

I'm not familiar with the 6920 barrel twist rate and what bullet range works best with it up to 100 yards. Maybe I'll see what I can find in the 62 grain range as I figure a heavier bullet would make a better defensive round anyway. But, it seems like 77 grains might be too heavy and will also stand to lose a good bit of velocity. (?)

I checked Midway and saw that the Wolf stuff sells for about $3.50 a box. Man, stuff that cheap scares me!!.....especially when you tell me it's dirty and it jams. Screw that. I don't mind going $5, 6, 7 or $8 bucks for better quality.

Posted: 5/23/2005 5:57:56 PM EDT

[#5]

Quoted:
I'm not familiar with the 6920 barrel twist rate and what bullet range works best with it up to 100 yards. Maybe I'll see what I can find in the 62 grain range as I figure a heavier bullet would make a better defensive round anyway. But, it seems like 77 grains might be too heavy and will also stand to lose a good bit of velocity. (?)

I checked Midway and saw that the Wolf stuff sells for about $3.50 a box. Man, stuff that cheap scares me!!.....especially when you tell me it's dirty and it jams. Screw that. I don't mind going $5, 6, 7 or $8 bucks for better quality.

IIRC, the 6920 is a 16" 1/7 M4 profile barrel. I shoot alot of 77gr stuff out of it and it is just fine. The 62 gr loads would be good out of that barrel also.

Posted: 5/23/2005 6:25:07 PM EDT

[#6]

Quoted:
I'm not familiar with the 6920 barrel twist rate and what bullet range works best with it up to 100 yards. Maybe I'll see what I can find in the 62 grain range as I figure a heavier bullet would make a better defensive round anyway. But, it seems like 77 grains might be too heavy and will also stand to lose a good bit of velocity. (?)

I checked Midway and saw that the Wolf stuff sells for about $3.50 a box. Man, stuff that cheap scares me!!.....especially when you tell me it's dirty and it jams.Screw that. I don't mind going $5, 6, 7 or $8 bucks for better quality.

Try Cabelas...1000 count is something like $130

I should clarify...I've experienced roughly 20 failure to feeds out of a case of 1000 (around 1 every two magazines).
My biggest issue was keeping the weapon clean. If you can hadle that, It's not the worst stuff for target ammo. I'd use it for when teaching inexperienced shooters, or when plinking.

Posted: 5/23/2005 6:37:29 PM EDT

[#7]

I get really good results with my SOCOM heavy barrel, 1/7 twist with 62 grain IMI ammo. I find IMI at the gun shows for around 4-6 dollars a box. Sometimes I can find really good bulk deals at gunbroker too.

Posted: 5/23/2005 6:46:58 PM EDT

[#8]

75 or 77 gr > *

go with 75 gr black hills or TAP

EDIT: zero it with that and use whatever cheaper stuff you want for regular blasting ammo, I use fed AE 55 gr for that. the point of impact between difference ammo at under 100 yds isnt that much anyway.

Posted: 5/23/2005 7:01:29 PM EDT

[#9]

Thanks guys for the input. It seems the 62 to 77 grain bullets will work from what I'm hearing here. (-I mean at least nobody is telling me to avoid it.) Whatever I try next would likely be the ammo I'd stick with and bet my life on. I'll see if Gander has something I can pick up quick while on my way to the range tomorrow. Anything over the 55 grains that I'm currently using, shoots clean and reliable, and costs$7-$10 will keep me happy. It sounds like there's plenty of stuff available for under $10

Posted: 5/23/2005 7:30:58 PM EDT

[#10]

Quoted:
Thanks guys for the input. It seems the 62 to 77 grain bullets will work from what I'm hearing here.

Not only will they work, It is my understanding that the 77gr Mk 262 Mod 1 (cannelured) is the deadliest thing out there right now in 5.56mm. More Army and Marine units are being issued mk 262, SOCOM already has been using it for some time.
Don't be surprised if it becomes the new standard military cartridge for 5.56mm weapons in the near future. This is far more likely than a caliber change to 6.8mm or anything else. The anecdotal reports I have read are talking about accurate kills out to 600m and more with this cartridge and a 20" 1-7 barrel. That's extremely unlikely with a comparable 55gr XM193 cartridge that will run out of steam at those ranges. Unfortunately the 77gr SMK Federal and BH cartridges are not inexpensive.

Posted: 5/23/2005 7:45:43 PM EDT

[#11]

American Eagle 62 grain FMJ

Posted: 5/23/2005 9:00:48 PM EDT

[#12]

Black Hills
77Gr. Sierra MatchKing molycoated HP's

Posted: 5/24/2005 7:09:19 PM EDT

[#13]

OK, now I am curious/concerned though about the 1-7 rifle twists in relation to the different bullet weights.

Do I understand it then that for 100 yard shooting, a 1-7 twist will stabalize any bullet weight from 55 grains to 77 just fine? For that matter, what would shoot best in my 1-9 barrel? ( I haven't fired that rifle yet.)

Posted: 5/25/2005 5:11:51 AM EDT

[#14]

No opinions on 1-7 barrel twists VS 1-9 twist and what bullet weights best stabalized with these twists?

Posted: 5/25/2005 5:37:13 AM EDT

[#15]

Quoted:
No opinions on 1-7 barrel twists VS 1-9 twist and what bullet weights best stabalized with these twists?

1/9 twist barrels work well w/ 40grn - 70 grn bullets (most 1/9s like Federal Gold Metal 69grn SMKs)
1/7 twist barrels work well w/ same weight rounds as 1/9, in addition to the heavier 75grn. MHPBT and 77 grn. OTMS & SMKs.

Mike

Posted: 5/25/2005 12:04:52 PM EDT

[#16]

I imagine a 6920 will shoot any heavy bullet you can find commmercially reloaded. It would probably shoot the 90gr SMK also, but you would have to load them yourself.

[ARCHIVED THREAD] - What's a good bullet weight and cartridge for my Colt 6920?

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