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Q&A 5

This is a LooseRounds.com Q&A session.  If you have a firearms related question please email it to [email protected]. We will post the your questions anonymously and give you our answers.

1.  Is it better to leave a few rounds out of magazines to save the spring?

Shawn- It is perfectly harmless to load  magazine to its full capacity. Springs wear form cycling , not from being under tension. Most of the time the problem in feeding is from faulty feed lips and not the spring.

Howard-  That started with the USGI 20 round mags which could have their spring installed backwards and would still function with 18 rounds, but would jam with 20.  Nowdays I would not buy or use mags that were not 100% reliable when loaded to capacity.

2.  What slings do  you recommend?

Howard-  First I would suggest reading Vickers article on slings.  It can be found here.  Shawn and I recommend for the AR15 slings like the Vickers sling, Viking Tactics sling, and similar 2 points.

3. How do you tighten the screws on a pre 64 Model 70 Winchester?

You tighten the front and rear screws the same as you would any other wood-stocked bolt action. but, the middle screw that holds the floor plate on is just barely tightened finger tight, just enough to let the floor plate close. if you tighten it much more it causes problems for the rifle.

4.  how do you use a weapon flash light

Howard-  Tactics and placement of a weapon light could be an article in it self.  However first a safety and employment.  I was working on a write up about it, however I found that Mas Ayoob beat me to it and did a better job.  I highly recommend looking at his article on the use of weapon lights that can be found here.

5. What is the best aimpoint for general use?

Howard- The answer depends on if you are running the aimpoint co-witness with iron sights, or without iron sights in the view of the window. If you are not co-witness with iron sights, I would highly recommend the Aimpoint T1 or H1 for its compact size and light weight. However if you are co-witnessessing with iron sights, a larger window is usually preferred. If you have the money, I would recommend the Aimpoint Comp M4, however the Aimpoint PRO offers similar excellent features at an economical price. The Aimpoint PRO is probably the best value for the person with a limited budget.

Colt 901 Part 4

In parts 1-3 Shawn has pretty much covered most of I would say.

Previously, I owned an Armalite AR10 model 10A4F and I replaced that with a LMT MWS which I quickly got rid of.

The Armalite was about $1500, and was a nice rifle.  However with its 20 inch barrel, A2 stock, and longer then AR15 action, it make for a long almost awkward rifle.  While it did deliver its guaranteed 1.5 MOA, it was neither the handy battle rifle I would have liked, nor a semi-auto precision rifle.  So I replaced it with a LMT MWS.  The MWS had some very nice features, but I had some issues with mine, and sold it quickly.

Now having tried the Colt 901, I much prefer the Colt over the previous two rifles I owned.  The 901 is surprisingly soft shooting.  That’s not to say that it doesn’t have recoil, but that it is a smooth impulse.  Perhaps the M1 Garand might be a good comparison.  The Armalite I owned was not that pleasant to shoot, and the MWS, while nice, was still a much sharper recoil impulse.  When shooting the 901 off of a Harris bipod, the rifle recoils straight back, making it easy to watch my impacts through the NightForce 2.5-10×24 scope I was using.  When shooting offhand with an Aimpoint T1, the 901 recoiled smoothly up and back, I want to say that the recoil impulse is smoother than shooting a M4 with M855.  I don’t want to make some claim that the rifle has light recoil, but I find it extremely fun and easy to shoot.

I have noticed some people questioning the choice of the Vortex flash hider on the 901.  I know it to be an excellent choice.  16 inch barreled 308s have a good deal of flash and blast depending on ammunition used.  This pronged flash hider helped break up the flash and concussion from the shorter barrel, and makes the rifle much more pleasant for those around the shooter.  While a pronged flash hider will ring(most noticeable when dry firing), it is not noticed when firing the rifle.

The 901 is not light, but in my opinion, it balances well.  The Armalite rifle felt very nose heavy.  The MWS, while similar weight, had most of its weight in its barrel, making the rifle far more awkward then the 901.  The 901 handles very similarly to a MK18/CQBR with Daniel Defense RIS II and a suppressor.  It is not light, but it feels far closer to that of a M4 then the MWS.  I found the 901 easier to shoot well then the MWS.

On a side note, when I tried DAG surplus 308 in the LMT MWS, I could only get 6 inch groups at 100 yards with it.  It got to the point where people were making fun of me with my performance with that rifle.  This same ammo gives me 2.5 inch groups in the 901.  So far, in my limited testing, the 901 seems less ammo sensitive then the MWS.

I spent much of the time shooting the rifle with a Magpul CTR stock, the VLTOR IMOD that came with it works very nicely as well.

The Colt 901 is an awesome rifle, but it is not perfect.  So there are some things you should know before you buy one.

1.  The 901 uses a non-standard height front sight, so it comes with a Troy micro rear sight.  Standard AR15 rear BUIS will not work unless you use a rail mounted front sight on the monolithic top rail.

2.  The area where the trigger pins are on the lower is reinforced.  This means if you replaced the trigger, you will want to use the slightly longer trigger pins that come with the 901s trigger.

3.  5.56 PRI Gasbuster charging handles will not work with the 901 lower.  It is unknown if the BCM gasbusting Gunfighter charging handles will work.

4.  The 901 comes with “Colt Spec” .308 PMags.  These Colt Spec mags have an over insertion prevention tab on them.  I primarily ran the 901 with standard Magpul 308 Pmags and had no issues.  When using the standard PMags, think just like using standard GI mags in an AR15, push into the mag well, then pull to make sure it is seated.  The Colt Spec mags are nice, but not mandatory.  With the upper removed, I found it was a non-issue.

5.  The quad rail on the 901 is tall and narrow.  I think that rail panels might not be a good choice for this rifle, but it does work well with ladder covers.  I think that LaRue index clips were a little too slick for the 901.  A Knights handstop and VFGs work well on the 901, but are lower from the bore then I am used too.(I mainly use the Daniel Defense RIS II rail).

6.  The 901 is nose heavy, however it is not too different then a M4 with accessories, or a SBR with suppressor.  I find it better balanced then many of the other .308 variants I have owned or used.

Please don’t read this list the wrong way, I HIGHLY recommend the 901.  It is good to know these sort of things before you buy the rifle.

What I am looking forward to most is having an SBR 901.  I am excited about having a 308 upper, and a short 5.56 upper in the same case, with a single .30 cal can I could run on both uppers.

Q&A Session 1

This is the first session of LooseRounds.com Q&A.  If you have a firearms related question please email it to [email protected]. We will post the your questions anonymously and give you our answers.

1. Aimpoint vs. Eotech?

Howard:  Shawn and I advocate the Aimpoint.  While early Eotechs were a far superior optic to early Aimpoint, modern Aimpoints easily beat Eotechs.  Aimpoints like the PRO, T-1, and Comp M4 have superior battery life over the Eotechs.  An Aimpoint will run for years while an Eotech will run for a month on a single battery.  In a recent drop test by Andrew Tuohy of http://vuurwapenblog.com/ the Aimpoint beat the Eotech.  Eotech has also had issues with battery draining while the optic is off.  Lastly, for a home defense rifle you can leave an Aimpoint on at all times so your rifle is ready to go.  I would not want to have to turn on an optic in a hurry while in an adverse situation.

2.  Will the Colt 901 take any 5.56 upper?

Shawn:  The Colt 901 will accept any 5.56/6.5/6.8/300BLK/etc upper receiver that has a small front pivot pin hole(Sorry, no old SP1 uppers will work with out an adapter).  You will need to use a mag well adapter and change out the buffer and buffer spring.

3.  Aimpoint PRO vs. Eotech.

Howard:  Ignoring the vs. Eotech part that was previously covered, the Aimpoint PRO is an great economical choice for a AR15.  Running about $400 new, it comes as a complete package ready to mount onto an AR15.  At 3/4 max brightness it will run about 3 years continuously.  You can leave this on next to your bed, or in your patrol car and know that it will be ready to go when you need it.  You can quickly adjust the brightness to be appropriated for the ambient lighting condition.  While it runs off a less common battery, you get so much longer life out of each battery it would end up costing you less then if you use an AA battery model Eotech.

4.  What is the lightest bullet for the 1 in 7 twist.

Shawn:  You can go as low as a 40 grain ballistic tip as long as it is a .224 bullet and not .223 hornet diameter, because the hornet diameter bullets have a light jacket designed to explode at a lower velocity.  Hornet bullets will not stand up to the faster twist and higher velocity.  Any quality 40 grain load will shoot just as well as any quality 55 or 62 grain load accuracy wise.  These lightweight bullets are not over stabilized and will not blow apart in flight.  That myth is from the days where people used the older light jacket hornet bullets in the new higher capacity .22 caliber cases like the .223 and 22-250.

Testing the 5.56mm MK318 MOD 0 / 5.56 SOST ammo

The 5.56 SOST  is the ammo currently being used by the USMC and other troops in the GWOT,  it has not been available for the public to buy for very long so I, like a lot of other people have been curious about how it performs. The round was designed to  have better terminal performance and accuracy from short barreled rifles with a muzzle velocity of 2925 fps from the 14.5 inch M4 barrel.  The round is a OTM,  this is important to remember as it is not the same as a hollow point.  It does however, offer up better performance and is barrier blind. The bullet itself has a thick copper base and a lead front end with the usual open tip that results from the process of making the bullet.  Also present are the rings seen around the bullet much like a barnes triple shock X.  A lot of people assumed and still do that the SOST is a barnes solid copper TSX, but it is not.

After getting my hands on some of the ammo I decided to test it for accuracy first. Since the ammo is intended for combat weapons, I chose to use my Colt 6940  with milspec barrel with 1/7 twist. I did put a Leupold 18x target scope on the carbine though so i could get all the accuracy out of it I could.  I fired 2 strings of 5 shots at 1 inch dots and one string of 10 shots of M855 to compare it to the common military load all at 100 yards. It was around 1100 AM , sunny with a  2 oclock 18 MPH wind.

Other then the normal 1st round flyer you usually get from hand cycling the action as opposed to letting the recoil operate and chamber  the next few rounds, the ammo showed some  great potential. The group on the left  was a little worse due to my own bad trigger work and lost concentration on one shot, but still pretty good considering. Now I know some claim  5 shot groups tell nothing, but if you over lay to  strings you get a pretty good idea  and you keep barrel heat down and mirage off the barrel messing with the scope.

After shooting the groups I decided to test out how the round matched the trajectory of the M855 since that is one of the things the SOST round was meant to have in common with the green tip. Out to 300and 400 yards  the SOST did match the BDC of my TA31F  ACOG and zero of other scopes and Aimpoint RDS I had on hand zeroed for the green tip. Also when comparing the position of the groups in relation to the aiming points, you can see on paper that the zero held very close for both rounds.

Now, the real surprise for me, was how good the lot of M855 I shot turned out to be!  Many gun board expurts and gun magazine expurtitions will gladly tell you how terrible green tip is in the accuracy department along with its many other flaws , makes it  slightly more useful then tits on a boar hog. After getting the carbine hot  after some drills using the SOST and playing around, I fired off 10 rounds fairly quickly  with the Colt/18x combo.  The results left me a little surprised, rarely have I seen green tip shot for accuracy  with sand bags, a table and a target scope further then 50 yards. And I do not recall having seen any pictures of it doing as well in a true 100 distance group.  I shot the green tip with all seriousness and the same concentrated effort I did with the SOST and the results were pleasing and a little surprising to me.  I have never taken the green tip seriously  enough for my own needs in the accuracy department so this will indeed lead to more testing of the M855 if for no other reason  then to see if this was a fluke.

Now I do not mean to sound like I think green tip is crap, I have seen some  good performance out of it at longer ranges on coyote size targets and even man sized targets. But on the other hand, I have seen some terrible accuracy from it too. Of course lots and different MGGs have as much to do with it as anything, not to metion the different shoots and the quality or lack of  in the guns used.

Back to the SOST, I think its a pretty good round from what I can tell. It is not MK 262 or TAP 75 gr. But for general issue to everyone, it is an iprovement in my humble opinion.  I have not shot anything living with it yet, but I will. Also, in the next few weeks I will test it though a few “barriers” like auto glass, wood, and wall paneling. Hopefully I will get to shoot through some auto doors as well.  I would not use it in my own house if over shooting is a issue, but I would use it for anything else at this point if you can find enough for SHTF bulk storing. And you have the benefit of practicing/training with M855 and still being able to shoot the SOST without a zero change. At this point I can not say it is better then any MK 262 top load in accuracy, but it is not meant to be, but, it is better then M193 by a long ways and it shows the ability to shoot a lot better the M855 and even if it just matches it in accuracy you still have the benefits of better terminal performance and barrier penetration while still holding together to hit the target behind if power point presentations can be believed. Hopefully my future testing will offer at least a tiny sample to help prove or disprove the new round.