5.56 Timeline

One way to break an Aimpoint T-1

Aimpoint T-1

I bought this used Aimpoint T-1, the former owner managed to turn the adjustment knob past the stops.

In this particular case, the optic works fine unless you rotate it past its limits.  If rotated past the limits it stops working until its turned another whole turn.

It is kind of rare to hear about broken or damaged Aimpoints, but if you abuse them, it can happen.  In this case the aftermarket battery cap had been cross threaded on and the optic was most likely damaged when it was forced off.


SWISS 7.5×55 Inert Training Rounds

Here is something you certainly do not see every day.  Arsenal dummy rounds  for use in 7.5×55 Swiss.  Used for training purposes and sundry.  The rounds have something inside that  gives them the sound of powder when you hold it close to the ear and shake.  And as you can see in the picture an indent for the firing pin to strike. The stripper clip is the usual construction  but painted red for ID’ing.  The charger for rifles before the adoption of the K-31.


TNVC/ARFCOM giveaway.

Prizes will be awarded on April 15th.

The Night Vision Company and AR15.com are doing a giveaway of multiple items including Night Vision,  a thermal Scope, an AR15, and more.

Click here to enter.

Here is the prize list:

Items in this giveaway will include:
– TNV-14 L3 Omni 8 Multicam – http://tnvc.com/shop/tnvpvs-14-l3-gen3-omni-viii/
– TNVC GoPro Adapter – http://tnvc.com/shop/nvg-adapter-for-gopro-hero-cameras/
– Team Wendy LTP Bump Helmet – http://tnvc.com/shop/team-wendy-exfil-ltp-bump-helmet/
– Wilcox G11 – http://tnvc.com/shop/wilcox-l4-g11-mount/
– TNVC Helmet Lanyard – http://tnvc.com/shop/tnvc-base-jump-lanyard/
– GoPro HERO 4 – http://tnvc.com/shop/gopro-hero4-silver/
– GoPro Blackout Housing – http://tnvc.com/shop/gopro-blackout-housing/

– ARFCOM 16″ 5.56/300BLK Billet Rifle (user’s choice) w/15″ BD Series Rail, Magpul grip/stock, custom laser engraving featuring AR15.com/TNVC logos
– Steiner DBAL-A3 Class 1 Laser System – http://tnvc.com/shop/steiner-dbal-a3-class13r-ir-laser/
– REAP-IR Mini Thermal Scope – http://tnvc.com/shop/ir-defense-reap-ir-35mm-mini-thermal-scope-640-x-480/
– Night Goggles Inc. Mini Recording Sytem with Tactial Rifle/Helmet Pouch – http://tnvc.com/shop/night-goggles-inc-mini-dvr-recording-system/


A Tale of a 20” Colt A2 Barrel

Originally posted by Molon on the AR15.com Forums:

Link to forum post.

A Tale of a 20” Colt A2 Barrel

This Colt 20” A2 barrel started its life on a factory-built Colt 6551. This was a pre-ban rifle, but this barrel did not have one of those evil, havoc-wreaking bayonet lugs; it’s otherwise essentially the same barrel found on the Colt M16A2 and M16A4 as well as “civilian” variants of those rifles. The barrel has a government profile, a chrome-lined NATO chamber and bore and a 1:7” twist.

I fired a couple hundred rounds through the barrel while zeroing, chronographing various loads and doing some informal shooting. I did not conduct a formal accuracy evaluation of the barrel at that point in time. After that, I replaced this barrel with a Colt M16A2 barrel with the attending evil bayonet lug to create my M16A2 clone.

This barrel sat on my parts shelf collecting dust for a while, until I decided to sell it. I ended up selling it over the Internet. Three months after the buyer received this barrel, he sent me a message demanding a full refund for the barrel claiming that the barrel was junk and that it was never going to shoot accurately. While I was under no obligation whatsoever to give the buyer a refund after having it in his possession for three months, I did so anyway, minus a “restocking fee.”

After the barrel was returned to me I decided to conduct a formal accuracy evaluation of the barrel. I installed the barrel on a Colt flat-top upper receiver and free-floated the barrel with a 12” KAC free-float hand-guard. I conducted the accuracy evaluation from a distance of 100 yards from my bench-rest set-up using my hand-loads topped with 55 grain Sierra BlitzKings.

This barrel turned in a 3-shot group at 100 yards with an extreme spread of 0.180”.

This barrel produced a 5-shot group at 100 yards with an extreme spread of 0.516”.

A 10-shot group fired from this barrel at a distance of 100 yards had an extreme spread of 1.085”.

Six 10-shot groups fired in a row from this barrel at a distance of 100 yards had an average 10-shot group extreme spread of 1.35”.

Not too shabby for a “junk” barrel and actually, as good as anyone could expect from a chrome-lined, NATO chambered government profile barrel. In fact, this was one of the most accurate 20” government profile barrels that I’ve ever tested.


The downside to the AR15 ambi-safety.


One of the overlooked but great advantages of the AR15 is its easy to actuate safety/selector switch.  Some other guns, actually most other guns have perfectly serviceable safeties but not ones that can so easily be used.  Because of this many teach to place the AR15 on safe often, even when reloading.  Now to debate the merit of that isn’t the point of this article.

Now when manipulating the rifle left handed or left handed only, I would use the thumb of the left hand to flip the safety off and I would leave it off until such time that I knew I was not going to need to immediately shoot.

It is not that awkward for me to flip the left side safety with the thumb of my left hand, but that is a brief moment when you don’t have a good grip on the gun.

So on many of my rifles I run ambi-safeties.  I’m rather fond of the KAC models with scalloped right sides.  I’ve also use or owned Colt, LMT, and DSA ambi safeties.

You would think that an ambi-safety would be a pure upgrade with no downside.  Unfortunate not.  The easy to reach AR15 safety/selector has the downside of moving through the same space that the trigger finger would occupy.

So regardless of if your trigger finger is on the trigger, or off the trigger pointed forward along side the lower, that safety lever can and most likely will hit your finger.

This is the reason why KAC offers a scalloped right side trigger and Colt’s ambi-safety is shorted on the right side, etc.  This helps a the safety clear the trigger finger of the right handed shooter.

So what if your left handed?  Sucks to be you.  Or you could buy one of those rather expensive completely customizable safeties.

Ultimately this is a training issue.  Regardless of the type of safety you run, you need to be able to actuate it one handed with either hand.  I found that it was rather different working the safety if your holding the rifle with both hands, vs working with the right single-handedly.  When your support hand is holding the bulk of the weapons weight, it is no problem to shift your firing hand as you work the safety.  However if your holding up your rifle with just the one hand, trying to move your grip as you toggle as safety is just plain awkward.