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 DPMS 308B iron sites
Toshu  [Member]
4/12/2010 12:37:34 PM
I will be the proud owner of a DPMS 308B fluted barrel gun in the next 10 days. Won it on Gunbroker.

What I would appreciate first is advice on sites. The gun has the higher flatside upper, and the gas block is a low one with rails such that the rail is below the level of th free float hadguard. I am planning on putting a scope on it, but want to see if it makes sense to put on a set of iron flip up sites . My concern is, will there be enough room/clearance with the scope/mount I will need, in order to use the iron sites with the scope mounted???

Obviously having back up sites to a scope ain't a bad idea either

Even if the sites can only be used without the scope mounted, what front flip up site is the best, in terms of clearance so that there is no interference with the view from the scope. Obviously I will have these for initial siting in as well as back up, so I do not want to buy the "most expensive" but the best value for the application.

Grizzman  [Team Member]
4/12/2010 12:53:02 PM
The solution for your gas block should be solved with a YHM or MI gas block flip up sight.....but that
really isn't a solution because they're designed to be used with a standard-height rear sight.

If you're gonna mount a typical long range scope and have a standard cheek rest, I don't know of any
rear flip up sights that'll fit under the objective......with the shorter rings due to the higher than standard
flat top. If you're planning to run an Aimpoint or ACOG, you shouldn't have any issues with that.

It it were me, (well I wouldn't have bought a 308 B in the first place) I'd get rid of the high rise upper and buy a
Fulton Armory 308 Titan upper.

Toshu  [Member]
4/12/2010 1:00:22 PM

that being said, what would you recommend with the YHM or MI front sight???

(I kinda figured that might be a problem.....)

I plan on testing the gun with a set of low scope rings and scope I have from an AR 15 223 for now with the existing rear stock. I am trying to keep costs down and things "simple"
Grizzman  [Team Member]
4/12/2010 1:04:33 PM
Wow, you were quick and posted while I was editing my original half-assed response.

Grizzman  [Team Member]
4/12/2010 1:53:26 PM
The MSRP on the stripped Titan slick side upper is $150 (plus the tools to swap them if you don't already have them) so that
would likely be the cheapest route to take to get a standardized upper. You can always sell your complete upper and buy
a complete upper based off a standard receiver, but that'll likely run more $$.

For the rear sight, you could use any AR unit that's short enough to fit under the scope. The trick is to use a standard AR-height mount for the scope. I run a Troy folding BUIS under the scope attached with a Larue LT-104 on my 308 and am very satisfied.

I've hard good things about YMH and MI, but have not used them myself.


Toshu  [Member]
4/12/2010 10:07:37 PM

it seems that with the configuration I got coming in, there is no sight set that will work, regardless of the scope, simply because of the high DPMS upper??? hmmm... what a bunch of bozos....

oh well, anything can be changed or sold...

I do have the tools for building standard AR 15s, built up 6 over 15 years ago, so unless the 308 needs something different, I should be okay for possibly changing the upper receiver...however, I will first see if with a scope, the barrel combination will work and give me tight groups....thats the key to start with..
Grizzman  [Team Member]
4/12/2010 10:23:50 PM
Hopefully someone else will have more experience with the 308 B and will be able to give a more positive answer.
pavlovwolf  [Team Member]
4/12/2010 10:51:58 PM
I would go with the Wilson Combat rear sight on this gun. I still have mine on my 6.8, but it was purchased for my LR 308. It is very solid. The main reason I chose this particular sight is that I was used to shooting long distances with Iron sights on my M1a rifles, and I wanted something that I could adjust for elevation changes easily. It also adjusts for windage. The front sight. I have had the YHM flip up on the front, but actually traded that to my son for his standard non flip Brownell's steel front sight. I changed to the magpul front for the 6.8 since it's rail mounted and not gas block mounted. The YHM moves a tad more than I'm comfortable with. I would never sell my Wilson rear, and have been offered right near purchase price several times at the range. I would recommend any front that locks solidly in place when in the raised position that is made from steel with the standard sight post.
pavlovwolf  [Team Member]
4/12/2010 11:01:15 PM
Mine had the high upper, I can give you the part for the YHM, as that is what I had on it. The Wilson rear is standard height. The YHM is the gas block model, and measures 2 inches tall when raised to put it in the correct position for the standard rear sight. Brownell's number is 100-002-089.
Toshu  [Member]
4/13/2010 9:13:21 AM
Originally Posted By pavlovwolf:
Mine had the high upper, I can give you the part for the YHM, as that is what I had on it. The Wilson rear is standard height. The YHM is the gas block model, and measures 2 inches tall when raised to put it in the correct position for the standard rear sight. Brownell's number is 100-002-089.

Just so I am clear on this, the sights you mentioned will work with a high DPMS slap side upper AND a LOW profile gas block rail, which is lower than the handguard???
Is that what your gun had??

pavlovwolf  [Team Member]
4/13/2010 1:16:43 PM
Yes, that's what mine had, if you're talking about the upper that's a tad bit higher, not the one that's really, really high. Look at your upper and tell me this. If you have the round aluminum handguards, does the rail part of the gas block sit just above the handguard? If that's the case, is the upper higher than that by just about the same amount, and does it have the two grooves running along the sides of the flat top portion where the charging handle is. If it does, it will work. I'd rather you post pics if you can, I can be sure that way. They had one really high one but it had three oval slots cut all the way through the receiver, but I don't know if they made that in .308, and it was called the high rider instead of the high rise.
Toshu  [Member]
4/13/2010 1:30:23 PM
here is the link to Gundbroker for the gun I bought

the pictures show the details
it looks like the upper may be the high riser???
pavlovwolf  [Team Member]
4/13/2010 2:05:44 PM
Yes, that's the same receiver I had on mine. I had the un-fluted 16" barrel with the flash hider though.That's the only difference. You will really enjoy it. Let me double check on that part number for you though. I keep all receipts somewhere. I had a very hard time trying to get info on what would work. Don't order one for the AR10 though, it will be too high, I made that mistake. DPMS didn't even know what was supposed to fit, and said it wasn't really designed for iron sights, so I actually ended up having to do a lot of math to figure it out, and finally got the right one.
Toshu  [Member]
4/13/2010 2:14:29 PM
but you did note in the photos that the front has block rail is Below the handguards......which sounds different from what you had said you had in the previous comment...


just want to make sure we are on the same "plane"
pavlovwolf  [Team Member]
4/13/2010 6:33:13 PM
O.K., I see what's going on here. Mine was the 308T, and the railed portion of the gas block sat just above the handguard. Yours is about 1/4 inch or so lower than the handguard, but the upper receivers are the same. What you need is list for the AR10. It was a tad too tall for mine. What you need then is the Midwest industries MCTAR-10-AFFG, ( Brownell's #100-002-984AF ), more than likely. Measure from the top of the rails on your receiver to a point about 4.5 cm high, that's about standard for rear sights when deployed. Do this while the gun is laying down so you can draw a line straight across to a point above the front gas block. Measure the distance from the top of the rails there to the line. That is how high the front sight should be, or very close to it, in order to work. You should be around 6 centimeters the way it looks. If you go with the Wilson combat rear that's adjustable for elevation that will give you a lot more adjustment room to take up any differences that might still be there. The DPMS set up you have is very close to the Armalite AR10 in the difference in sight height. Maybe someone on here has done this before with what you have. My rail was just a tad taller than the handguard, but within a 1/4 or so. I hope this helps. Midway list the sight as the AR10 front sight. It was too tall for mine, so it should work for you.
Grizzman  [Team Member]
4/13/2010 10:50:29 PM
I thought of a different option for you.

Model: 308-GB-SR9 Link to gas Block

Info from DPMS's website:

Correct height for the slick sided upper to attach iron sights.

Not correct height for the .308 A3 Upper

It's MSRP is $70, and I presume it'll let you run any front sight you want.

I'm still not sure that the rear sight will work under the occular lens of your scope without the scope being too tall for a good cheek weld.

pavlovwolf  [Team Member]
4/13/2010 11:43:33 PM
That's the same gas block that I had on the 308t that I had. It will still be lower than the rear since the rear is raised. He would need the first YHM sight I mentioned, or the medium, MI sight. He just needs the tallest of the three that MI has available.