Doing A Jig: IF YOU WANT TO UPGRADE YOUR GAS BLOCK TO A PINNED MODEL, BRD ENGINEERING'S JIGS WILL HELP YOU GET THE JOB DONE.
Even so, I am not a big fan of gas blocks with set screws due to the potential for failure. Over time, firing vibrations will do their best to loosen bolts and screws used to secure things to any autoloading rifle, including the AR-15.
A much more secure way of mounting a gas block is to pin it in place. This is how Eugene Stoner intended the gas block to be secured, and that's how the U.S. military does it.
What happens if a gas block comes loose? Loss of gas pressure will lead to functioning problems. Once loose, a gas block can move under recoil, and if the barrel's gas port becomes misaligned with the port in the block, the rifle will cease to function--ruining your range day at best, putting you in danger in a self-defense situation at worst.
Many years ago I spoke with master pistolsmith and retired U.S. Army Special Forces veteran Larry Vickers about this matter. "If you understand how the AR family works, you realize that any gas leakage is potentially disastrous," he said. "A set screw on a gas block is begging for it, and on a fighting gun it is a no-go."
Vickers recommends a pinned gas block, and some companies, such as LWRCI, offer rifles so equipped. But what if you want to build your own rifle or want to replace the set-screw gas block on your factory rifle?
Properly drilling through a gas block and barrel for a cross pin is no easy matter. It typically is a job best left to a good gunsmith, which is why most home builders opt to install a set-screw block--dab on some thread locker, tighten a couple screws and call it good.
There is another option, though. A small, family-run company out of Grand Rapids, Minnesota, BRD Engineering (BRDengineering.com), offers an AR gas-block drilling jig that allows a builder to drill a gas block and barrel easily to accept a cross pin. The jig allows you to do this with nothing more than a simple hand drill.
I spoke with owner Jake Carlson, a mechanical engineer who does all the design work on BRD's products as well as in-house machining and finishing. His wife, Katie, handles taking orders and shipping.
The company's history reaches back to 2006 when Jake posed a question on AR15.coM regarding the need for a dimpling jig. A decade down the road BRD Engineering now offers dimple jigs (if you want to go the set-screw route) and drilling jigs for a wide variety of gas blocks--along with other products.
I'm a fan of Geissele's low-profile gas blocks, so I ordered a drilling jig for this design. To use, you simply slide the jig into place on your gas block already fitted to your barrel. The robust steel jig will surround the gas block and fits precisely. Once it is in place, tighten the plastic-tipped retaining screw. Next secure the jig in a vise, and you are ready to drill.
Using a 3/16-inch diameter drill bit and good-quality sulfurized cutting oil, slowly drill through the gas block and barrel. Take your time.
Once you are through, once you've cleaned up the mess left behind by the drilling process, drive the pin that came with your gas block home while supporting the gas block with a piece of wood.
BRD Engineering's jigs turn a job few home builders will tackle into something that takes but a couple minutes. The end results look professional while adding some welcome peace of mind knowing your gas block is properly secured.
BRD Engineering offers everything you need for supplies, including jigs for a host of different makes of gas blocks, drill bits and cross pins. If you will be drilling into a Melonite-treated barrel, BRD highly recommends using carbide drill bits. Price-wise, both jigs start at $60 each.
Caption: BRD Engineering offers a dimpling jig (l., for set screws) and a drilling jig for properly mounting a pinned AR gas block (r.). After drilling using just a handheld drill you can secure the gas block with a cross pin.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||TACTICAL TECHNOLOGY|
|Publication:||Petersen's Rifle Shooter|
|Date:||Nov 1, 2017|
|Previous Article:||Charge! THE NEW RCBS CHARGEMASTER LITE DISPENSER IS THE BEST VALUE ON THE MARKET.|
|Next Article:||ARE YOU READY FOR THE COUNTRY? WINCHESTER DRESSES UP ITS AFFORDABLE XPR TO CREATE THE NEW HUNTER MOUNTAIN COUNTRY RANGE.|