Kieler Militia Supply is here to educate the masses on their rights and help shed light on firearms. We are here to support the "Unorganized Militia" and "Organized Militia". --“I ask who are the militia? They consist now of the whole people, except a few public officers.” – George Mason, Address to the Virginia Ratifying Convention, June 4, 1788


Monday, July 22, 2019

Fixing my brother's AR15 Accuracy Issues

My Brother's AR 15 was built from a Daytona Tactical kit and they are OK. No real gripe about the quality of parts or anything, but at the range the supplied upper receiver was sent assembled and I noticed accuracy issues. One thing led to another and I disassembled to see what was going on. 

What I noticed after the barrel nut was loosened was the excessive amount of play between the barrel extension and the receiver. Any amount of play in this area can lead to accuracy issues as well as the face of the receiver if it is not flush and true when mating barrel to the upper receiver. 

This rifle was very light and had the best muzzle brake on the market yet was shooting horrible groups at the range at 100 yards. Very wide.

Now there are many ways of fixing play like this. I have seen people use aircraft grade epoxy on the barrel extension then lathe it down to perfect fit. I have also seen people use 609 Loctite and also 620 Loctite, but in the event where if we decided to change the barrel down the road that would seem difficult to release. What I decided to do was go the old school way of doing things and that is by shimming the barrel. Many competition shooters from the past used this method when M16's were used in shooting competitions in the Army. To achieve accuracy everything must be a snug fit. Any play between barrel and receiver can cause accuracy issues.  

But before shimming you need to verify trueness of the face of the receiver to the barrel extension.

Some receivers need lapping. 

Breaking it down.


Using 220 grit lapping compound I lapped it by hand. 

Shimming the barrel fitment with an aluminum can Shim.

Now the barrel has a perfect fit, nice and snug. 

Wide spread before. Mind you this this with Winchester 5.56 before. 

and this is after. 

1.5 - 2 inch group at 100 yards with non match cheap Winchester bulk ammo. It will be better with it not being 90 degrees and having Match grade ammo. 

Other improvements to the rifle came from Nictaylor00 Adjustable Trigger kit

Best investment you'll ever have for under 20.00

Trigger Improvement Spring installation for milspec triggers. No need to spend 200.00 to compete.

This kit takes the draw out of the trigger. 

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