Talking Point: Bolt Carrier Group

A couple of small points regarding cleaning the bolt carrier group.  I see some people who recommend removing the extractor and gas rings on the bolt with every cleaning.  I don't recommend this...the potential damage to the retaining pin of the extractor or to the gas rings is high.  The retaining pin in my opinion isn't designed to be removed frequently and could start to fit loose if removed too often.  As for the gas rings, they have to be flexed quite a bit to remove them, and could be ruined.  For cleaning these area's, I just saturate them with Hoppe's 9 and it does a great job...sometimes a little compressed air helps to move the junk out.

Proper lubrication of the bolt carrier group is essential to long life of the AR.  I've circled the areas in red where I apply a liberal amount of oil.  The bolt carrier rides on the 4 ridges that run along the front sides, I add a generous amount of oil here, and also along the side of the bolt key.  Coat the entire cam pin with oil.  On the bolt itself I add a couple drops of oil to the gas rings, and to the ridge in the middle and work it all the way around for even coverage (the bolt should slide smoothly once inside the bolt carrier).  I place a light coat of oil to the face of the bolt, the retaining pin, and the shaft of the charging handle.  As for the firing pin, that just needs a very light coat of oil on it.

Remember, keep the bolt carrier group well oiled and it will keep your gun happy!

An excellent blog on precision shooting

I stumbled across this blog last night, and spent a couple hours reading the excellent posts.  Check it out...

http://riflemansjournal.blogspot.com/

Gun Rights, Mexico and Libya

I am troubled by our government trying to take away our 2nd amendment rights using the 'flood of US guns into Mexico' as one possible method to start our disarming...
http://www.nraila.org/legislation/read.aspx?id=4632

and then they turn around and consider giving guns to 'rebels' in Libya?
http://www.bbc.co.uk/news/world-africa-12902450


Libya BOMBED Pan-Am flight 103.  Gaddafi didn't put the bomb on that plane personally...it was an action by people of Libya.  Now we want to arm the 'good rebels' to overthrow Gaddafi?  We didn't take him out ourselves in 1988, or 1989...etc....  Instead, we are going to arm these people....willingly???

Am I missing something??  Is this OK because Libya isn't on our border? 

The US needs to STOP PUNISHING THE GOOD PEOPLE OF THE UNITED STATES, and THINK LONG AND HARD ABOUT WHO THEY WILLINGLY HAND WEAPONS TO OUTSIDE OF OUR COUNTRY.

Target

I have been looking for a target that fits my needs, but nothing was exactly what I was looking for, so I decided to make one.  The circles are sized to what I feel are the 'vitals' size for small game, coyote, and deer.  I have also placed a couple of boxes for defensive practice...the inner which I consider 'good hits' and the outter as 'acceptable'.  Tick marks are at 1" intervals.  (I can email the PDF on request.)

Please see my update here => http://ar15shooter.blogspot.com/2011/04/target-v2.html

Sight height to muzzle considerations

The sight height in relation to the muzzle will alter the impact point of a bullet in relation to the point of aim at distances away from the zero point. A high sight line does not however decrease precision, you just need to understand the effect of sight height to muzzle distance.

Remember that bullets fly in an arc as they move from the muzzle to target, which means that at a given distance, your bullet will impact at a different point than your point of aim. The bullet will pass the point of aim at 2 points, once as it passes the sight line heading up (your initial zero crossing), and then again as the bullet drops after apogee (your zero sighting distance). This can be seen in the following chart.

Consider an AR-15 with iron sights and a carry handle mounted scope. The iron sight sits 2.65 inches above the center of the bore, and the scope sits 3.65 inches above the center of the bore. The point of impact using a 55grain bullet, zeroed at 225 yards for both scope and iron sight, compared to the point of aim is given on this chart: You will notice that when using the scope, the bullet 'starts' at -3.65 inches below the sight line. This is an inch lower than the sight line used with the iron sights. When you zero both sights at the same distance, what you have in effect done is set your rifle to fire at a slightly higher angle for the scope (when mounted higher than the iron sights). The bullet still hits at the same point at 225 yards, but will take a slightly different path to get there.

Cleaning Kits

I've tried a few different systems for cleaning my rifles, and in my opinion there is only one worth spending $ on....the Otis Technology system.


http://www.otisgun.com/pc_product_detail.asp?key=A143AFCDD3F7420D971E1FCE78ACEFD7

Why I love this kit...

It's super compact, your always cleaning from chamber to muzzle (so your not pushing junk towards your trigger group), the kit works with all of my various caliber rifles, and it works really good!


After finding this kit, an article ran in the newspaper about the company that makes these things...I was happy to see that buying this product supports an Upstate NY company!
http://www.syracuse.com/progress/index.ssf/2011/02/otis_technology.html

So you want to buy an AR-15?

First off, this is just my general advice, and I recommend to everyone -> get the advice of many people before you purchase...my experience is limited to my DTI AR-15 (which was highly recommended by my local gunshop), and my reading and observations of other brands. I'm just another voice in the crowd, and by no means a supreme authority.


Whenever friends get a chance to shoot the AR, they are hooked and want to pick one up....because it's just fun to shoot! I have a few pieces of advice to keep in mind when you start shopping.

What you want is a mil-spec AR-15, and they are made by many manufacturers. Wheather it's from DTI (Delton), Bushmaster, Colt, DPMS, Stag, Smith & Wesson, or coutless others...the general form of an AR-15 is the same....and if they are built to mil-spec, then the parts are compatible with each other (for the most part). I can take the upper receiver of my friends AR-15, and attach it to the lower receiver from my DTI, and the gun will function perfectly!

First, get your AR-15 chambered for 5.56 NATO. If it's chambered 5.56 you can shoot .223 Remington in it, but you can not go the other way around!

Determine what style you desire for your application, this will point you towards a long rifle, or a shorter carbine, as well as the weight of barrel you need. Aside from quality of manufacture, I see this as the only major consideration...as every part of the rifle is upgradeable...if you don't like the grip....change it.....trigger blows...change it (a friend has a Timney trigger and loves it).....want that quad rail up front....add it later....it's no big deal. Even the front sight/gas block can be changed down the road if you want to mount a scope to the rail, and get the front sight out of the way.

This leads to the next consideration...upper receiver type, and in my opinion anyone buying today should get a picatinny rail upper reciever...if you like the carry handle look of the AR, then you can add one....but if it's an integral part of the reciever, your stuck with it.

Beyond this, I feel the choices start to become highly personal. I like the AR 'all black', though I know people who have the OD Green grips, and it looks nice...but it's just not me. I also like the looks of the collapseable stock carbines (though mine looks adjustable, it is fixed, NY feels a collapseable stock is 'evil'), the other major option is the classic rifle stock...along with many aftermarket stocks. The AR becomes a very personal weapon as you build it up.
As far as sights go...I feel you definatly have to have iron sights...even if it isn't your primary tool, you should have backup iron sights...and you should know how to use them effectively.

Accuracy

A lot of people ask 'how accurate are you'...I'm a beginner, and I get better every time I go out to practice. With my Savage 17HMR, I am doing sub 1 MOA using a front sandbag rest. With the AR-15...I'm running sub 4 MOA...at 50 yards using a front rest, I managed a 10 shot group of 1.7". Acceptable, but I wouldn't call it 'good'. But like I said, everything improves with practice.

Keep in mind with this picture, at 50 yards my AR is shooting about 1.1" low, so it is the tightness of the group that is of interest here, not the bulls eye.
And in my opinion, you should judge your accuracy based on 10 rounds, and not 3....anyone can get lucky....but 10 times in a row starts to show what your made of.

Excellent reading on the history of the AR-15

I highly recommend this book to anyone interested in the history and development of the AR-15 platform.

The Complete AR-15/M16 Sourcebook: What Every Shooter Needs To Know by: Duncan Long
http://www.amazon.com/Complete-AR-15-M16-Sourcebook-Shooter/dp/0873646878

Scope DOPE

Knowing your DOPE, or Data On Personal Equipment is important when it comes to shooting your rifle accurately. Since the bullet travels in an arc, the point of impact compared to your point of aim will vary with distance. As a side note...the bullet initially travels upwards before it starts heading down...this isn't due to 'aerodynamic lift' it is due to the fact that bullets are fired in a slight upward angle.

I like to use the Nikon scope calculator (located here http://www.nikonhunting.com/SpotOnRegistration/ ) to generate my STARTING ballistic curves. These values serve as starting points, and will need to be fine tuned with live fire at your shooting range.

I write these values onto a chart which i then cover with clear packing tape (to help waterproof it), and then adhere it to the inside of my scope cap, that way it's always on hand when your using your rifle.

I sight in my scope at 225 yards which keeps me within -3.65" at close range (the distance of my muzzle to scope center) and a maximum of 1.2" at 155 yards....which will keep me well within the 'vitals' for self defensive use. With my setup, the bullet passes the sight line at 80 and 225 yards.

AR-15 with Karsten Cheek Rest

As a first post to my 'AR-15 Shooter' blog, installation of my new Karsten Cheek Rest (available from http://karstenskydexcheekrest.com/ ) seems like a good place to start!

Using the carry handle mounted scope on my AR-15 didn't allow for a good cheek weld, and was adversly affecting my aim. In searching for a solution on the net, I came across the Karsten Cheek Rest, and ordered one up. I'm very happy with the design and build quality of the piece, and the price was right!

Installing the rest on my AR-15 carbine did present one challenge....with the buffer tube running down the center of the stock, I had to drill the holes pretty low on the stock, and this location did now allow the riser to compress and grip the stock. My solution was to use nylon spacers available from Lowes to fill in the space and provide centering to the riser. They did not have 3/4" spacers so I superglued a 1/4" and 1/2" spacer together to do the job.

I then drilled two 1/4" holes in my stock, one that widened the existing 'strap slot', and a new hole towards the front. Be sure to drill the hole low enough so the spacer will sit flush against the stock.

The setup works great, and gives me an extra 8/10" of rise above the existing stock, exactly what I needed!

I also glued on a piece of leather to the top of the rest using 3M Hi-Strength 90 Spray Adhesive (lay the leather face down and spray on the adhesive directly to the back, then stick the leather to the cheek riser). I found the leather at Jo-Anns Fabrics, and trimmed it down to fit...it's a much nicer feel than cold plastic on your cheek.