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Slinger
03-01-08, 13:27
I bought a S&W15 Optic Ready AR. Nice gun. Shoots well and all that. Bought a Yankee Hill folding rear and Brownells flip-up front sight. Went to zero it at 50 yards.......... With the front sight post screwed IN/DOWN all the way it's still hitting 16" low. I ran a straightedge from the flat top to the railed gas block and they are the same height. Can two different sight mfgs. be that far off to make them incompatable? I was trying to get off cheap, because I won't use them that often. Mounting a red dot on it for primary use.

RCHyde
03-01-08, 13:41
Check the model # of your front sight. There are two differnet types- one is the correct height for mounting on gas blocks, the other is for mounting on the top forearm rail. Sounds like you have a front sight for a gas block which would be slightly taller.

Slinger
03-01-08, 14:24
Yes, it's mounted on the gas block rail. I'll check Brownells catalog, but I didn't see but the one front sight of their brand.

DM-SC
03-01-08, 16:16
Is this the one you have?

http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=23318&title=AR-15/M16%20TACTICAL%20FLIP%20UP%20SIGHTS

It should be correct for mounting on a gas block. I guess you'll need to call the folks at Brownell's...:(

watertower
03-01-08, 17:05
I've got a similar problem with an ARMS #40 and a Troy and LMT front sight. I know I've got the correct front sights (both rail mounted), but with both front sights when bottomed out still hit 8" low at 25 yards.

I'm interested in hearing from others that might have figured out a good way to fix this.

Slinger
03-01-08, 18:16
Is this the one you have?

http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=23318&title=AR-15/M16%20TACTICAL%20FLIP%20UP%20SIGHTS

It should be correct for mounting on a gas block. I guess you'll need to call the folks at Brownell's...:(

Yes, that's the front sight. But they dropped the rear sights they're showing in the picture, so I ordered a YHM- Brownells # 100-002-094, but something's not jiving with this combo. I was going to buy the Midwest front & rear, but didn't want to spend the extra money.

Slinger
03-01-08, 18:24
I've got a similar problem with an ARMS #40 and a Troy and LMT front sight. I know I've got the correct front sights (both rail mounted), but with both front sights when bottomed out still hit 8" low at 25 yards.

I'm interested in hearing from others that might have figured out a good way to fix this.

I'll post if I come up with an answer.

G19A3
03-01-08, 18:28
shouldn't the front sight be "unscrewed" up for the point of impact to hit lower?

Slinger
03-01-08, 18:33
Mine is 16" low at 50 yards. In order to raise poi you have to lower the front sight. Mine is as far down as it can go.

watertower
03-01-08, 18:37
shouldn't the front sight be "unscrewed" up for the point of impact to hit lower?

That is correct. Move the rear sight in the direction you want the impact of the bullet to move. The front sight is moved in the opposite direction you want the impact to go.

The problem Slinger and I both have, is that we're out of adjustment, and POI is still way too low.

Slinger
03-01-08, 19:05
If it was only a matter of a couple inches, you could get away with filing down the front sight post. But @ 8" or 16" low, there probably wouldn't be much of the post left

DM-SC
03-01-08, 21:33
Yes, that's the front sight. But they dropped the rear sights they're showing in the picture, so I ordered a YHM- Brownells # 100-002-094, but something's not jiving with this combo. I was going to buy the Midwest front & rear, but didn't want to spend the extra money.

I can't imagine why they'd make it that way but, I wonder if those front and rear needed to be used as a set. There's nothing stating so in the description but, that is a different looking rear that they were selling. :confused:

Slinger
03-01-08, 21:37
I even talked to a tech guy before I ordered the sights. He never said anything other than they dropped the rear sight. I think my problem is the the gas block rail on my S&W optic ready is the same height as the flat top receiver. So I have to have sights that are compatable with that mounting plane. I'll find out Monday.

RCHyde
03-02-08, 07:10
Sounds like S&W is using a non-standard height gas block. See if you can return the front sight and exchange it for a forearm model from MI, Troy, or YHM.

Slinger
03-02-08, 07:44
I'm going to try MI front sight forearm model. I have a YH rear that I'm sending back. Doesn't lock up solidly in the "UP" position. I think I'll call MI tomorrow morning to get their take on it.