As mentioned elsewhere the current DPMS LR-308 receiver picatinny rail height is not compatible with most aftermarket handguards. Most attempt tso replace the factory forearm will result in rail heights that are not on the same plane.
Fortunately there are some new product’s on the way to change this situation.
I have created a new page devoted to help you determine which reciever you have as well as keep you up to date with the current aftermarket options. That page is here.
This is one of my pet peeves. Guys go out and spend a $1000-$3500 of their hard earned cash getting their 308 AR just the way they like it. Then proceed to buy the cheapest possible ammunition they can find. Then they are surprised when the rifle wont function correctly.
Below is a scenario that plays out constantly in my inbox and forum.
Guy heads out to the range and is surprised when his shiny new rifle fails to function properly. He then bring the rifle home fiddle to with it, maybe get some opinions from friends or the internet and heads back to the range for more of the same. Inevitably either on his own or from gathering opinions the need to try an alternate ammunition become apparent. once again off to the range for more of the same. Now the shooter is angry that he spent all this money on a rifle that wont run. In anger he will call the weapon manufacturer tech support hotline. In most cases tech support will steer him to try a different magazine and maybe even another brand of ammunition. Back to the range and maybe the new magazine helped a little, small encouraging signs but the gun is basically a single shot. Back home and the shooter is livid back on the phone with the manufacturer for an RMA number. Two months later the gun will return with a note stating the chamber was polished. Our excited shooter heads back to the range and the rifle still doesn’t function properly.
First off DPMS has gone so far as publish a list of AMMUNITION NOT TO USE IN ANY DPMS RIFLE INCLUDING THE LR-308.
Here is that list
After extensive testing, we have found that only ammunition manufactured to SAAMI (Sporting Arms and Ammunition Manufacturers Institute) specifications is reliable in DPMS rifles. DPMS recommends the use of high quality, domestically produced ammunition for best results and highest accuracy. For plinking and practice, we recommend only domestic, commercially manufactured ammunition. Please note: the use of hand-loaded ammunition voids the factory warranty. The use of all ammunition listed below also voids the warranty.
We have incurred feeding problems with the following:
- Israeli ammunition
- Korean ammunition
- Chilean ammunition
- Portugese ammunition
- South African produced surplus
- Lacquer Coated Ammunition or Steel-cased, lacquer coated ammunition
- Silver Bear
- Any steel-cased (coated or non-coated) ammunition
We have reviewed several reports, from several manufacturers’, regarding problems using this ammunition. The problem appears to be the bullet contour and the overall length of the cartridge, which is contacting the rifling before firing. This is creating a gas port pressure and chamber pressure higher than recommended, therefore causing feeding and extraction problems due to the increased bolt carrier velocity. In addition, there is accelerated fatigue on internal parts. There are also indications that brass may be out of spec, which could create an unsafe condition.
We have used this ammunition in the past for testing purposes and found the brass is extremely soft and can “flow” into microscopic pores and grooves in the chamber creating “sticky” extraction. This has been reported in many types of rifles, but is more prevalent in semi-automatic weapons.
The problem with this ammunition is that the lacquer coating on the case. As the barrel heats up, the lacquer turns to a soft, varnish substance and upon cool down, becomes very solid and difficult to remove. This effectively creates an undersized chamber and creates understandable problems.
Your rifle is an investment and it only makes sense to choose quality ammunition for a quality rifle!
First off should you really be surprised when an ammunition that costs 1/4 to 1/2 the price of domestic ammunition fails to function properly in a weapon? I think not. Secondly you can swap one inferior brand for another and expect the same result.
What’s the point of shooting this ammunition other than cost? It’s not accurate despite most internet reports to the contrary. It’s not consistent from one lot to the next. So even if you manage to get a good batch it’s no guarantee the next lot will be any good. The ammunition is dirty as hell and possibly corrosive unless you believe the print on the box. You cant stake your life on it in a SHTF situation.
I’m not saying you need to run out and buy Federal Gold Medal Match but you need to use some common sense. For cheap 308 ammunition look to one of the generic domestics such as Federal American Eagle or Winchester USA. If that’s still to pricey the PRVI PARTIZAN brand offers excellent value and accuracy. Avoid anything that has an animal in it’s name.
I think DPMS sums it up in one sentence. Your rifle is an investment and it only makes sense to choose quality ammunition for a quality rifle!
Advice for a 308 AR that wont cycle properly
If your 308 AR is DPMS compatible the simplest way to verify your 308 AR functions properly is to buy a MAGPUL 308 PMAG and few boxes of premium ammunition. The PMAG eliminates the possibility of a magazine issue as they are nearly perfect and the premium ammunition will be clean burning and accurate which will help you get that new 308 AR broken in and functioning like a champ. If you have an Armalite omit the magazine as there are no alternatives.
Note: A new 308 AR needs a lot more lubrication then an AR-15. Put some Mobil 1 on the bolt carrier and bolt ot maybe even your favorite gun grease on the bolt lugs. The BCG should be almost dripping wet with oil for the first few hundred rounds.
The SI DEFENSE GENERATION II STRIPPED 308 UPPER RECEIVER is 100 percent DPMS LR-308 parts compatible. The picatinney rail is of correct height opposed to the new DPMS height. I haven’t a clue what the side picatinney rail is for. This is the upper in use.
After only a few short weeks my of waiting the MEGA ARMS MA-TEN 308 AR RECEIVER SET arrived exactly as scheduled. My first impressions out of the box is very good. The units have been manufactured and finished flawlessly. The MEGA ARMS MA-TEN 308 AR RECEIVER SET will be used in the #3 308 AR build project at 308AR.com.
MEGA ARMS MA-TEN 308 AR RECEIVER SET
Sun Devil MFG has begun production of DPMS pattern 308 AR receivers.
Here is a quote directly from Sun Devil MFG
We are machining the .308 lowers now. We should have the uppers ready to machine in 60 to 90 days. The MSRP is $249.95 for the lower. They look very similar to our AR15 receivers. They are DPMS compatible and they also have the tension screw.
This 308 AR rifle build is an intermediate stage of another project. The plan is to use a matching SI Defense Generation II Upper and Lower Receiver, but at this time the lower is not in my possession. So for curiosity sake I took the SI Defense Upper and installed it on my DPMS LR-308 Lower from my DPMS LR-308 Precision Rifle Project on this site.
The upper consists of the following hardware:
- SI DEFENSE GENERATION II STRIPPED UPPER RECEIVER
- DPMS 308-BL-SASS 18″ FLUTED BARREL and MATCHING SASS GAS BLOCK GB-SASS
- JP/VTAC JPHG-6D JP Modular Hand Guard, Extra Long 15.5
- DPMS 308-BCA Bolt Carrier Group
Pro Mag DPMS LR-308 SR-25 .308 WIN 20 RD MAG
I noticed Brownells is stocking the new Pro Mag DPMS LR-308 SR-25 .308 Winchester 20 round magazines. They are priced directly between the Magpul 308 PMAGS and DPMS LR-308 factory magazines.
- CONSTRUCTED OF HEAT TREATED STEEL WITH A PARKERIZED FINISH FOR DURABILITY AND HARSH USE IN THE FIELD
- SILICONE WIRE SPRING AND PRECISION MOLDED POLYMER FOLLOWER ENSURE RELIABLE FEEDING & FUNCTION
- FITS ONLY DPMS .308
Ambidextrous Safety Selector AR-15 AR-10
The Bad Ass Ambi Safety Selector is Oversized, Deeply Grooved Levers For Positive Operation With Either Hand.
Machined, heat-treated steel safety selector has oversized contact pads on both sides of the receiver for easy ambidextrous operation. Large surface area lets you manage the safety while wearing gloves, and eliminates fumbling in the dark. Pads are deeply grooved for an ultra-secure grip under stress or when hand is wet. Can be customized by positioning the larger pad on either side of the receiver or with the application of high-visibility paint. Mounting hardware included.
So you gut your shiny brand new DPMS LR-308 home from the gun shop. You love everything about it except one thing. The upper and lower receiver have slop just like all of your AR-15’s. So you think to yourself “on my AR-15’s I usually by those fancy adjustable pins or I cheap out and get an Accu-Wedge” but this is a BIG AR in .308 this must require something much more sophisticated or something bigger. Well guess what? The Accu-Wedge works in the DPMS LR-308. In fact the factory suggests it and sells it as. Fulton Armory also sells a device called the Accu-Wedge on their 308 Titan pages. See a pattern here?
Note:If you decide to install an Accu-Wedge in your 308 AR you might have to trim it a little to fit.