LR 308 front sight and height

[blue109]

if it says A3, it's going to be a standard height receiver. to clarify...it will be the new DPMS height, also known as the low DPMS height. any front sights or gas blocks designed to match a standard AR15 will match this rcvr. the light weight one looks to be pretty close to a standard piece, with some metal milled off of it.

[N Jensen]

I uploaded 6 photos. The upper is an old LR receiver where the flat top is higher up for mounting a scope over a standard flat top receiver. I used a Lipski rear sight base where it is adjustable in height to either have the rear sight mounted very high or very low to the relationship of the flat top. The rear sight is an old RPA match rear sight with a merit aperture disk to allow adjustment size hole/circle to look through to the front sight and the target.  The front sight is a MCS with an adjustable iris and a .03/.05 diopter on the front side of the sight. So I can adj rear sight opening and front sight size based on light conditions and size of the target. 

 

The one photo of the target is NRA Long Range target that I shot at 1,000 yds. Each paster represents a bullet hole that was pasted over as I fired my 2 sighter shots and 20 shots for record/score. The ten ring is a 20 inch circle while the xring is a 10 inch circle. The one nine at 7 o clock was after lowering my elevation one minute as I was shooting a nice group in the ten ring at 2 o clock. I was worried it might shoot low and it did, so I came back up the 1 MOA and left my elevation alone after that stupid mistake. In the vertical displacement I have 11 shots within 1 MOA or 10 inches, the remainder of the shots are within 2 MOA except for the two shots in the nine ring and the one was of my stupid mistake. Not bad for a semi auto and iron sights to boot. I mentioned modifying the bolt to work without gas rings, this rifle never shot this good before I did the mod. I know there are skeptics out there, but a picture helps once in awhile.    

 

You might say shooting iron sights at  1000yds would be hard to see the target. I use a .05 diopter in the front sight which acts like a magnifier glass. Many times I can actually see the white 6 inch spotter stuck in my last bullet hole through the sights at 1,000yds. While aiming it actually makes me work harder on the sight picture as I can see the spotter on the target.

 

The lipski sight comes in either the RPA mounting or standard Redfield mount. Creedmoor sports, Brownells and white oak arms sell them. Match Rear sights are out there for sale, they don't make the RPA any longer, but they come up for sale on ebay or gun broker once in awhile. Brownells sells the PNW and Champion Choice as well.

 

Hope this helps you.

Edited April 29, 2014 by N Jensen

[blue109]

I can't even fathom shooting 1000yds with irons. that's pretty manly.

[survivalshop]

Impressive ! 

[N Jensen]

gnatshooter

I wanted to ask you if the photo helped. I have a good stock weld for 200 yds through to 600 yds. If I shoot 1,000yds, I lower the front sight about 21 MOA or .168. I use a veneer calipers to make the adjustment. When done I raise it back up the same amount for short range shooting. Doing this allows a good stock weld for 1000yds by making the major adj on the front sight instead of the rear sight.

Thanks for the compliment on shooting. I remember shooting my M1A at 100oyds, I used to swap out the front sight with a very short post so I could keep a good stock weld. There are solutions to everything, just takes time to decide what is the best solution to what you want to do.

[gnatshooter]

gnatshooter

I wanted to ask you if the photo helped. I have a good stock weld for 200 yds through to 600 yds. If I shoot 1,000yds, I lower the front sight about 21 MOA or .168. .

 

Those photos helped. Unfortunately, I just can't get used to shooting with a rear aperture -- I grew up with a notched rear leaf. The sight I'm working with now comes with a notched rear leaf and I had to have a machinist cut a leaf for me with a smaller notch. AFAIK I have the only fully adjustable rear leaf on the market for an AR-type rifle, with a notch compatible with a longer sight radius, so to get that rear sight lower my only option is to get a different upper receiver. I have been unable to find a dovetail riser to work with the Lipski barrel band on the front.

[N Jensen]

Roger that, hope it goes well for you.

[gnatshooter]

Friends,

 

I'm on the brink of ordering a new low-profile upper for my DPMS LR-308 but before I do that, I'd like to make sure I really have the high-profile upper.

 

Could one of you with a DPMS low-profile upper put a calipers on it briefly? Just release the pivot pin and measure from the bottom of the upper receiver to the top of the rail, and get back to me.

 

Doing that measurement on my current upper -- accused of being high-profile -- gives me 2.375".

 

Thanks!

[blue109]

http://762ar.com/wp-content/uploads/2011/09/DPMS_RECEIVER_HEIGHTS.jpg Edited May 1, 2014 by blue109

[gnatshooter]

http://762ar.com/wp-content/uploads/2011/09/DPMS_RECEIVER_HEIGHTS.jpg

 

That link redirects to http://762ar.com/303_error.htm

and gives me the error message "Forbidden action"

[blue109]

sorry, try this. these are the 2 versions of the A3 height. I'm guessing yours is closer to 1/2" at that spot.

[gnatshooter]

sorry, try this. these are the 2 versions of the A3 height. I'm guessing yours is closer to 1/2" at that spot.

 

You're right! My upper is not pictured in that pic -- the portion of the upper above the charging handle on my rifle measures 0.535". How'd you know that?

 

Now, how do I know which version of the A3 I would get if I ordered the upper DPMS has here for only $125? Would that be the 'low A3' or the 'lower A3'? I'd be wanting to go as low as they get. If I ask DPMS I'll probably get the same response from them as I got earlier on a similar question: "You're over-thinking this."

[blue109]

you will get the lower one unless it has been sitting on a shelf in the warehouse for 5 years. the lower profile is the new DPMS standard. has the same height over bore as a standard AR15, so setting up irons will be much easier.

[survivalshop]

  DPMS makes or made a high railed upper receiver , similar to the # 4 photo in  N Jensens post above . He has a high railed receiver , that is probably the 1/2" measurement , which is probably what you have .  Now is your front sight set up for it , like N.Jensens or is it set up for one of the shorter rail heights , is the question.

 If you want as low as you can get , then the A3 upper is what you want, can't get any lower , to my knowledge . 

 The link you have to the DPMS upper seems to be an AR 15 & not a AR 308  though they will have the same upper rail height.

[gnatshooter]

Many thanks, dudes!

Edited May 1, 2014 by gnatshooter

[blue109]

like SS said...your link for the $125 upper is a 5.56, not a .308. making sure you caught that.

[gnatshooter]

like SS said...your link for the $125 upper is a 5.56, not a .308. making sure you caught that.

 

I went back and looked, yes, you're right. Funny thing though, the .308 and 5.56 uppers have the same part number.

[gnatshooter]

Friends,

I thought I would finish this thread off the right way, with a list of what I ordered. Interestingly, some Forward Assist parts come from the LR 308 portion of the DPMS online store, and some come from the .223/5.56 section of their online store. I called DPMS on the phone to confirm that this is indeed correct and that these parts do indeed go together. I think you'll agree that I got a good deal from DPMS.

308-FTT-EA .308 A3 Receiver (Stripped) $169.95

308-UR-07 .308 Forward Assist Spring $1.75

UR-06 Forward Assist Pin $0.75

UR-08-RA Forward Assist (Round) $13.95

Taxes: $13.07

 

Shipping: free on orders over $50

 

TOTAL: $199.47

 

I did not get an ejection port cover, because most people on the 'net say it's either in the way, or breaks/bends easy, or both. DPMS offers a port cover for this receiver.

Edited May 2, 2014 by gnatshooter

[survivalshop]

Friends,

I thought I would finish this thread off the right way, with a list of what I ordered. Interestingly, some Forward Assist parts come from the LR 308 portion of the DPMS online store, and some come from the .223/5.56 section of their online store. I called DPMS on the phone to confirm that this is indeed correct and that these parts do indeed go together. I think you'll agree that I got a good deal from DPMS.

308-FTT-EA .308 A3 Receiver (Stripped) $169.95

308-UR-07 .308 Forward Assist Spring $1.75

UR-06 Forward Assist Pin $0.75

UR-08-RA Forward Assist (Round) $13.95

Taxes: $13.07

 

Shipping: free on orders over $50

 

TOTAL: $199.47

 

I did not get an ejection port cover, because most people on the 'net say it's either in the way, or breaks/bends easy, or both. DPMS offers a port cover for this receiver. 

 

I've done a lot with these AR rifles & can't say I have ever had a problem with an ejection port cover , But its not really needed for a target type rifle.

Edited May 2, 2014 by survivalshop

[gnatshooter]

Survivalshop,

 

At least my options are still open. There's a lot of various advertising that people offer for stuff on the ejection port cover. Like, 'Molon Labe' or 'Death to Zombies', etc. A cover in solid brass would probably get my money, just cuz.

Edited May 2, 2014 by gnatshooter

[392heminut]

 

At least my options are still open. There's a lot of various advertising that people offer for stuff on the ejection port cover. Like, 'Molon Labe' or 'Death to Zombies', etc.

Keep in mind the AR-15 covers won't work, the AR 308's have a larger port and use a larger cover.

Edited May 3, 2014 by 392heminut

[gnatshooter]

I guess this would be a P.S. I got the low-profile upper receiver from DPMS in record time. They'd warned of a 2-3 week delay and I got the thing in 7 days.

 

The local gunsmith, who's trying to retire and is only open 2 days a week, 6 hours per each day, swapped out the upper receivers in a couple hours at a cost of $80.25 -- all labor. I'd already installed the forward assist, so that wasn't part of the deal. That was kinda painful, but still -- I didn't want to buy tools I would only buy once for one job.

 

But the result is the important thing. I did the Bore Sight Boogie all over again and found that my front sight is now nice and robust. Looks like a range rifle, but strong enough for woods-running. Works perfectly with my rear sight.

 

And things worked out as Blue noted -- the issue of getting a cheek weld when the iron sights are too tall. Thanks, Blue! The sights are now low enough that I get a nice cheek weld and will no longer be looking at the Magpul PRS because of the adjustable cheek riser.

 

I still might look hard at the simply because it looks like it offers a shorter length of pull on the stripped version. I'm not built like a bull, and chasing Bambi's mom through the woods with an LR-308T is job enough. A shorter pull will make it easier to bring the rifle's center of gravity closer to my 'center of muscles'. You've probably seen right-handed shooters with the left hand under the barrel shroud and the left elbow in their gut. That's me.

 

And, hunting is all about offhand shooting. When I was a kid, I practiced like crazy and shot amazing groups, I was just that kind of kid. And shooting offhand is how you bring home rabbits and squirrels. Well, I gotta get back to that if I'm gonna bring home Bambi's mom's steaks.

 

With the length of the buffer tube on an LR-308, there's only so much you can do with the length of pull.

 

Sorry for writing so much, but dang, this change in receivers really made a difference that I intend to enjoy.

[blue109]

far as shorter LOP...an A1 length stock is as short as you are going to get with a rifle length extension. those adjustable lop stocks can only go longer. if you don't want to go with a standard A1 stock, check out the vltor rifle modstock, the M.A.G.S. EFX A1, or ACE. three very different designs in A1 length.

Edited May 15, 2014 by blue109

[survivalshop]

Good job . Glad you got it all together .

 

Those port covers with the sayings are kinda cool , the BRO upper I am going to order( I have a BRO lower ) , has "LET IT RAIN " on it , but of course that has to do with the manufacturer , Black Rain Ordinance .

Solid brass might be on the heavy side for a port cover , but a plated one would not add much to one . That would have that special look .

[blue109]

I have one that says TEAM AMERICA when it's closed, and FûCK YEAH when it's open.