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Old November 1, 2018, 02:21 PM   #1
Willie Lowman
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18" BCM awesomeness

A friend and I are always trading guns. Last year I got a Colt 6920 for some surplus .30-06 ammo. Just last week I traded a MP5 pistol for some cash and a BCM 18" upper that he wasn't using. So I put a SSA trigger in the 6920, slapped the BCM upper on it and mounted a Trijicon Accupower 1-8. That done I went out to the farm to sight it in.

I was frustrated initially. I put a shoot-n-see target at 50 yards and missed the whole target with every shot. Moved the target to 30 yards and again I wasn't even on paper. Moved the target to 10 yards and finally got hits far right and high. I cranked on the turrets, moved the target, adjusted, moved the target again... After a slow start I made it back to 50 yards where I made my initial zero. Once I was happy with that I put another shoot-n-see at 200 yards and loaded the rifle with some Mag-Tech 77 grain ammo.

When I saw my 200 yard groups I was really happy! The worst was 2 1/4" and the best was 1 1/2". I feel this is pretty good for the first time I have fired this particular rifle. If the rain stops this weekend I am going to take it back out and see what I can do.

I am concerned about the scope mount though. In order to get the eye relief I wanted, I had to put the front of the mount onto the first 1/2" of the handguard rail. I have been told to never bridge a mount between the receiver and the handguard. So I am worried about how my scope is mounted but it doesn't seem to have caused a problem yet.
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Old November 1, 2018, 07:08 PM   #2
Nathan
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Pics?

Just wondering, why was the BCM Upper a better choice than the Colt?


Was the optic NIB? What mount?

The concern you speak of is two fold....First, even with 4” of eye relief, I find the ocular lens even with the back of the upper...So, you may be craning your neck or practicing poor head/neck/shoulder position..

Second, if you are mounted on rings, no way front ring and rear are properly aligned. This usually shows up in scope damage or awkward turret movement.
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Old November 2, 2018, 06:17 AM   #3
Mobuck
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"Just wondering, why was the BCM Upper a better choice than the Colt?"

IMHO, there are numerous "better choices than COLT".
Maybe my "prancing pony" experiences aren't the same as others.
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Old November 2, 2018, 12:52 PM   #4
Willie Lowman
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The rifle as is.

The overlap of the mount onto the handguard.
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Old November 2, 2018, 01:22 PM   #5
Willie Lowman
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Quote:
Just wondering, why was the BCM Upper a better choice than the Colt?


Was the optic NIB? What mount?
The BCM is a stainless 18" barrel that's free floated and has a rifle length gas system. For something that I will likely be shooting suppressed, that's a better choice than a 16" carbine upper.

The scope mount is a Trijicon 34mm Bobro mount.

As for craning my neck; when I shoot prone my nose almost touches the charging handle. I have to hold my head back to get a full view through the scope. As you can see in the pic I have the scope mounted an inch forward of the back of the receiver. This position gives me a good view when shooting prone. Any further back and I get a black ring around my reticle.
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