Tag Archives: Gun

How Does a Striker-Fired Pistol Work?

This is an impressive and thorough breakdown of the key components of a striker-fired pistol and shows cutaway animations of each component plus animates the entire mechanism in action. 

Not bad for 1:30. Congratulations- you’re now smarter or at least briefly entertained.

Tactical AR reloads

Good video on tac reloads here. No empty mag-throwing pageantry just good fundamentals. My only question is why would anyone ever train to reload using the first method shown in each example?

It seems to me that a tactical reload – i.e. one where your mag is not yet empty- would be the time where you would want to bring that fresh mag up to the one you're about to remove. It doesn't make sense to me to leave the gun limited to the chambered round for that extra time- even during a lull in the action. The economy of motion should result in a faster mag change too.

 

Do you really need a bipod?

I bought a low-end UTG bipod for my rifle and have used it quite a bit. The 6″ legs work ok in some scenarios- (they were outstanding when setting up on a gravel pile and pretty much any soft surface is well-suited to a bipod)..but at the bench at my local range it's too tall. I frequently end up adding a wood block to my chair to get my body as tall as the gun when I use my bipod.

Of course that's for 5.56, 300 BLK, and other small arms calibers- where its easy to 'lean into' the bipod to minimize bounce. With something a little larger like a bolt action .308 with a free floated barrel and a very cheap, flexible (and lightweight, don't care if you scratch it…) stock a new problem emerges when you're on a solid surface like a shooting bench: bipod bounce. The combination of tall bipod, flexible stock and larger caliber was resulting in a wild bounce that left me staring downrange pretty far off target. There has to be a better way. In fact there are several:

Bags

A popular method for resolving this is to use shooting bags. It makes sense- nice sandbags you can use to make a solid and low rest for your rifle. Many recommend using a bag under the forearm and a bag under the stock.

This isn't a bad approach- it certainy promotes the support hand-under-the stock technique that I am quickly growing to like. Still I am not thrilled about adding another 20-40 lbs of weight to my range gear. Also what about a situation where you probably don't have bags with you (uh, like hunting?) – what are you supposed to do at that point? The answer is pretty simple and turns out to be useful pretty much everywhere:

Backpack

Yep- a plain old backpack. This is tribal knowledge- my father learned this from a Gunsite instructor and passed it along to me. Internal or no frame is best- and its typically nice to have something soft in the pack to help with his purpose. Jump is a non-factor when using a backpack as a rest off a bench. This is a smart and fast method to deploy for a shot and it can be used virtually anywhere- even on a soft surface.

  • Lay the pack down with the long side facing down (You can stand your pack upright for a kneeling shot). Simply hit the pack with your arm to create an indentation.
  • Lay the rifle forearm down into the indentation- slide it forward up to the trigger guard if you can. This will reduce your chances of pulling the muzzle back too far- muzzle blast is not friendly to backpacks or their contents.
  • Place your support hand under the stock of the rifle. You may find that placing the stock between your thumb and first finger is the most effective hold.
  • The support hand now can control the elevation of your rifle. Left-Right should be controlled by the 'cradle' you created and slid the rifle into.

 

My current dry fire drill

Road construction derailed my trip to the local range earlier this week. Now what? For me it becomes 25 good dry fire reps. Recently I started using the second drill shown in this video- the empty shell method(keep a couple in your pocket to keep the drill moving). You get a few ancillary benefits from this drill:

  • You must hold the gun steady the whole time or the shell will fall
  • Include presentation in your reps. This requires a ton of stability the entire time you clasp the support hand and raise the pistol to your sight picture. This practice can help if you have to take a close-proximity defensive shot or shoot from a restricted position- like inside your vehicle
  • Trigger press needs to stay smooth throughout this drill- that balancing shell is not going to stay upright

 

WTF is this thing?

While this double trigger mod does not inspire me to rush out to order one it claims to have lots of benefits:

  • The lower trigger has a pull weight 50 to 60 percent lower than that of a standard trigger
  • It fits any mil-spec AR-15 with a removable trigger
  • The reduction in trigger weight makes precision shooting easier

It was also inspired by a paintball device, fwiw. At any rate something like this is pretty much like adding a BAD lever to your AR- in the sense that once you add one you have officially changed your firing mechanics.

Barrel Twist: why does it matter?

A lot of people at ranges across America are probably couldn't tell you what the barrel twist rate is or their rifle without looking. As noted above, barrel twist is the number of inches spanned in one complete rifling rotation- iow how fast is your projectile spinning by the time it exits the muzzle? Twist rate is commonly noted as a ratio- for example 1:8 (the preferred 300 BLK twist rate- especially if you want to shoot subsonic ammo). Barrel Twist also has an effect on the projectile weight you use:

Common barrel twists for 5.56 AR-15 rifles:

1:9 – does not stabilize heavier projectiles well (55gr and up- you will see 'keyhole' hits on your targets); stabilizes lighter projectiles extremely well (like varmint bullets)

1:7 – stabilizes heavier projectiles well ; stabilizes light projectiles well enough. You can't go wrong with a 1:7- that's what the US Military uses.

Common barrel twists for .308 Bolt Action rifles

When shopping for bolt actions twist becomes an important consideration if you want to be able to use and experiment with subsonic loads. Bolt actions can have different twist rates (and barrel lengths – which also factors into stability with heavy projectiles) than the ones listed here so it's worth some investigation before you make a decision.

1:16 – will not stabilize a heavy subsonic projectile (200gr and higher) in .308

1:10- will nicely stabilize a heavy subsonic projectile and also stabilize lighter projectiles well enough

Common barrel twists for 300 BLK (AR-15 platform) rifles

1:8 – this does the trick and supports whatever you send downrange regardless of the muzzle velocity

1:10 might stabilize a 200gr projectile at subsonic speeds but you are severely limited in projectiles with a 1:10 BLK barrel

The bottom line here is that you should be certain that your 300 Blackout kit has a 1:8 barrel- there isn't a good reason not to.

Defensive Training Tip: Practice from inside a vehicle

The video above illustrates some of the dynamics you should consider about how to react if you need to defend yourself from inside a vehicle. The clip is from TTAGs Nick Leghorn at Gunsite- So you know it's reputable technique.

Look at how constrained the draw and fire motions are- without practice this will be far from intuitive for me. While you may not be able to practice live fire from your vehicle and don't have a 'shoot car' handy like the Gunsite Academy this can still be practiced with an unloaded weapon – just make sure that you:

  • Always triple-check your carry piece to be sure its unloaded
  • Are not out in public view (in the garage with door closed perhaps or in a secluded area)
  • Practice with drivers window open and closed– if that's how you tend to drive

Indestructible Training recently ran a car-based IDPA stage and noted the awkwardness he observed among many of the people on his squad. There is an easy remedy for this – practice it until you get comfortable and confident. How much time do you spend in your car every week?

Criminals are crafty- they will seek out times and places where you are in more compromised positions to attack- like when you're in a vehicle as that constrains your movement possibilities. If that sounds unreasonable to you watch this clip : not only does it showcase the critical importance of situational awareness (watch the bad guys creep past and stop around the corner) and how quickly this successful DGU occurs.

 

 

This is why the carbine ‘magwell grip’ is not ideal

In the video above Travis Haley demonstrates a couple carbine handgrip positions and fires splits with each. Watch how wobbly the rifle is with the magwell grip- thats not for me.

Look at the C-Clamp grip illustrated below. The support hand forms a “C” with the thumb on top of the handguard and as far forward as you can safely place it. Now lean into the gun- aggressive stance- you will find that you can get rounds on target faster and keep the muzzle down more effectively. No more wobble!!

 

IDPA drill: target transitions

This is a nice video covering target transition tips. The key here is to start with the nearest and leftmost target- nearest because it is the threat with the closest proximity and leftmost because the gun will move up and to the right as every shot breaks. Work with the momentum of the gun and your technique will be smoother- in this case aiding in smooth transition from left to right target engagement.

American Defense Manufacturing: troubleshooting my co-witness

After my recent post covering research and decisions on setting up a co-witness sighting system I ran into a problem. When I tried to achieve a co-witness view through my Trijicon RMR (on an American Defense Mfg riser) it looked like this:

Where is the front sight? Why is the amber triangle so low in the RMR? This sight picture is way to low to be a lower 1/3, much less an absolute co-witness.

I talked with the armorer at my LGS (local gun store) and we covered a bunch of diagnostic questions. Specifically:

  • Is the upper a continuous rail from upper receiver to end of handguard? <yes>
  • Was the upper factory assembled or built at home <factory assembled>
  • Are you holding the gun properly?
  • Your nose should be touching the charging handle when you acquire a sight picture. That is the method I was using.
  • Are the sights standard height?
    • I used Troy Battlesights- fixed front sight and flip-up rear. Both are standard height. Troy does make micro sights now that are not a standard height- don't use these for a co-witness because they are very short.

    We ruled out all those common causes of a problem like this. What's left? The actual co-witness riser mount appears to be too high.

    To be certain the armorer grabbed an Aimpoint T1 and put it on the rail next to the RMR. The mount heights were indeed different. Next he removed the RMR and looked through the aimpoint. Sure enough there was the front sight – centered in the reticle as expected for a co-witness.

    I got in touch with the folks at ADM (American Defense Manufacturing) to explain the situation. They were very easy to work with and after hearing a recap of the troubleshooting they made my day. ADM has offered to build me a new mount to my specification. I measured up the mount and the sight plane and asked them to take about .250 off the existing design.

    I hope to have the new mount back in hand in about 2 weeks. American Defense really went the distance to make this right– I am now a customer for life and suggest you give them a hard look if you're looking for any mounts, rails, etc. Although if you're looking for an RMR co-witness riser you might want to specify that you want the low one…