D9Firearms Custom LR-10 (DPMS, Mike Rock Barrel, White Oak Armament)
Saturday, May 31st, 2008
Over the last few months when advertising our D9Firearms customized DPMS LR-308B we received multiple inquires from our clients interested in a DPMS LR-308 with a 20” SST bull barrel. After a few requests we decided to investigate some possible options and consulted one of our good friends, who is an Army Ranger, whom we will refer to as Tool, on some possible barrel makers and features.
Tool immediately suggested White Oak Armament (WOA), so we decided to give them a call. We spoke with John, who is extremely knowledgeable and took the time to explain several issues and give me some ideas and issues to consider when designing a barrel for a semi-commercial purpose.
Basing some of my design criteria on the Army’s M24 sniper rifle, which Tool provided us with (no they weren’t Army secrets otherwise I would had to take him out), I wanted to go with the 11.5 the same as the M24, but after speaking with John, cost and practicality dictated I went with a 1-11 twist rate. (After doing some more research the .5” extra twist rate would not add any value or performance other than saying “I have an 11.5 twist rate and you don’t”.) (Just like the Army to come up with something like that.)
I put together a sketch ran it by Tool and then called John to finalize it. John gave me a few more things to consider before finalizing the design. The issues I was struggling with were the benefits of fluting and which barrel manufacturer to use.
With fluting, the question is there any noticeable performance benefits or degradation? After reading several articles from engineers, barrel makers, and shooters I determined that fluting is more for ascetics on certain configurations and weight reduction on others; however none suggested degradation of the barrel or accuracy.
Since our barrel is going to have a .980”dia on the main body and necked down to a .920 on the fore end, we would have had to cut deep flutes in the main body to achieve any significant weight reduction, which John did not recommend. So I opted for shallow fluting on the fore end of the barrel primarily for ascetics. (I think it looks cool and personally I am willing to pay a few extra dollars, and no I don’t have spinners on my rims or a grill when I smile, a little urban lingo there.)
The final issue was selecting a barrel blank. Depending on whom you speak with and what you read, you will get a full spectrum of opinions, which were all free. After consulting Tool and John again, I evaluated from cost, quality, commercial considerations, and results John had with these manufacturers.
Our goal was to stay in the mid to high quality without overpricing ourselves. The choices from the low end up were:
- Wilson
- Shilen
- Pac Nor
- Kreiger
- Mike Rock
The spread was about $150 difference from the Wilson to Mike Rock.
Mike Rock is a name known to more of the industrial shooters such as our good friend Tool. Wilson would be a good choice if I decided to go for a more competitively priced rifle, but since I am risking putting my name on the product, standing behind the work, and my capital expense to develop and build five of these, I decided to go with what the heavy hitters prefer and went with Mike Rock blanks.
One difference on the blanks I chose from Mike Rock is that those blanks will be a cut rifled barrel and not buttoned rifle. The difference is that the rifle cut barrels require more time, precision, and are not as much of a production style operation where as the button rifled barrels are. (I could use this as marketing hype but in the end either process using a precision barrel maker will provide repeatable 3rd eye style results on any insurgent’s forehead.)
To finish off our barrels, John will head space and gauge our barrels to the bolts I shipped to him to insure all tolerances are met.
The final specs on our barrels are:
- Mike Rock blank - 20” SST bull barrel.
- Gas port based on the AR10 at 11.6”.
- Fore end fluting.
- Threaded barrel.
Since we’ve been doing this for quite some time we have no reservations standing behind our work, since it won’t be warranted by DPMS. However, we know what a manufacturing defect is and will offer basically the same warranty. If you abuse this, put hot loads through it, or use it for any other operation other then its intended purpose, you own the rifle.
However, treated properly this rifle will last you a lifetime and deliver precession results expected of any bolt gun with the added benefit of immediate follow up shots in the event there are multiple targets. This rifle will be the epitome of the Marine Corps motto; “One Shot, One Kill”. (Even though we used some of the Army’s data.)
The final stage of this process is customizing the remaining features on the rifle. Some possible configurations: (All standard parts including receivers, springs & detent pins will be factory new DPMS parts.)
The base rifle will include:
- DPMS Lower receiver assembly
- Mike Rock barrel
- Double rifle case
- Two 20 round magazines, & cleaning kit
- Shipping
- Everything else will be a la carte
- $1300
Stocks:
- ACE SOCOM AP4 ($185)
- Magpul PRS ($225)
- CAA 6 Pos Collapsible ($50)
- Standard A2 fixed stock ($50)
Hand Guards:
- DPMS extended 4 rail ($180)
- Badger Ordnance Stabilizer hand guard ($180)
- JP rifles Vtac extended ($170)
- Daniel Defense 4 rail ($389)
- DPMS Round Aluminum ($60)
Gas Blocks:
- Koelbl ($35)
- JP adjustable ($80)
- CMMG micro ($60)
Flash Hiders:
- Panther flash hider ($40)
- Miculek compensator ($60)
- Others are available upon request
Grips:
- CAA G-27 ($30)
- Hogue ($22)
- Panther tactical ($35)
Triggers:
- JP Adjustable w/speed hammer ($185)
- Rock River 2 stage National Match ($120)
- Jewel 2 stage Adjustable ($225)
- Timney single stage ($220)
Miscellaneous:
- Tactical bolt release ($20)
- Tactical safety ($25)
- Ambi safety ($35)
- Tactical mag release ($20)
- Anti-walk trigger pins ($10)
Upper Receiver:
- DPMS Slick Side ($390)
- DPMS A3 Flat top ($440)
- (Both include chrome bolt carrier, bolt, charging handle, tactical carrier release)
Optics:
- IOR Valdada
- Night Force
- Horus Vision
- Your choice
If you are interested in purchasing one of these rifles please contact us here at D9Firearms. We will have 4 of these available (I have to have one) late July.
Thanks

















