The Tale of a Rifle and a Load

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12 years 5 months ago - 12 years 5 months ago #11683 by zfk55
The Tale of a Rifle and a Load was created by zfk55
The Tale of a Rifle, It's Performance and Load Data.

For 10 years my Father dogged the originator of the Armalite Wilson AR10. After reading an article on the man and his rifle in 1999, he contacted the Gent and found that he was not selling to the public. His clientele were the Marines, Army and Contract Companies operating in war zones. Despite being turned down, he continued with intermittent contact for a 10 year period, all to no avail.

One day, while sitting in the armoury and talking to my Dad, I noticed the pages of a magazine sticking out the end of a manila folder. I asked what it was and he explained about Stewart Wilson's AR10s with the 16" barrels shooting moa at 1,000 yards and photos of the Marine Team that was testing them. "Hey! We need one of those". After hearing the tale of his trying to secure one, I suggested we call, write or email Mr. Wilson. Dad told me it was an excercise in futility, but after searching the net we found a website, shooterready.com that was a long distance training DVD and, sur enough. It belonged to Mr.Wilson. By the third email he agreed to sell Dad a rifle "because you've been dogging me for all those years", but if the price was questioned the deal was off. We didn't question the price and witin a few weeks we had the rifle and the first 10 shots on the supplied proof target. .685 moa.

Since then he and Dad have become friends and it's nice to have an inside track with Mr.Wilson. He's the Father of the Windrunner .408 series of rifles and designed the product line for EDM Firearms. My rifle is the prototype of those rifles, but with a lot of options not available on the production model. Ok, so this isn't about all that. It's about the journey to the sub-moa at 1,000 yards the rifle was/is guaranteed to do. It came with the target, specific load data and specific case prep and reloading requirements. Enter.... me.

These are the original specs on the rifle:
She has a custom, internally re-machined Armalite AR10 receiver/magazine well cut to accept a slightly longer AR10 custom magazine, this because of the required OAL.
All internal receiver areas are coated with a Tungsten Disulfide Matrix derivative. The chamber and throat are cut to accept one projectile profile only. The Sierra 175 MK,
and no other. Because of these cuts the TTL, seat depth and OAL are specific and critical, thus the need and reason for a custom machined Mag-well.
Walther 17-4 S/S barrel, internally tapered .006 electro-polished bore and a 1-10 ROT. Moly Specific.
SWS foregrip and a prototype trigger from his inventory that later evolved into the Chip McCormick trigger.

The following is the sequence and history of some 1,550 chrono'd and logged in rounds sent downrange, some of which were moa in 5 round groups, but I wandered in and out of moa to 2moa week after week with intermittent strings of amazing sub-moa runs. I was getting frustrated. I'll make this as short as I can.
We used the original Load Data, case prep and the cases themselves were not easy to get. They were to be Lake City headstamped "LR". Those are the USMC Long Range cases that are once fired and collected by a specific case and projectile supplier. Prep, shoot... no moa, change the load by 1/10gr increments up and down...... moa once in a while.

This is what we tried:
Powder charge change in 1/10gr increments to 2gr under and 2gr over intial data.
TTL OAL
Bushing change
Seat depth changes
Seat depth and charge changes to 2gr under and 2gr over intial data.... Chrono spread literally tight with the original data, IE: 2505fps. SD +-7
The above amounted to some 1,500 rounds with one critical change midway through. We found that our Moly process, similar to Sierra's was not deep or hard enough. You should be able to go 3 to 400 rounds without seeing any coppering of the lands/grooves at all. Dad changed his process and the coppering after 160 rounds disappeared, but still no consistent moa shooting. I was discouraged to say the least. I was about ready to stack it in the armoury and work with my M1 Garand for a while, until..............

I'm down prone in the shootshed and Dad said he'd been watching my shooting technique all along and judged it solid and correct, but today he had an idea. He had me remove my prescription shooting glasses, put on my contacts and fire 5 rounds. MOA!! We went back to the armoury and reloaded 20 of the original load data we had on day one! 4 moa groups right out of the gate! Back to the armoury for another 20 rounds.........But this time, he had me remove my contacts. Sub-moa! Back for another 10, same results sub-moa, group after group!

So, 1,550 175SMK projectiles, pounds of powder, frustration and disappointment was all traced back to something so simple we hadn't considered it. Contacts and prescription shooting glasses. Those contacts did a slight floating action on my lenses and the shooting glasses changed with my prone head position. I could move my head slightly and got a better, sharper picture. That should have told me something, but I never imagined it.
The Wilson performs exactly as designed, and I'm an extremely happy camper. A lot of component dollars lighter.... but happy.
Last edit: 12 years 5 months ago by zfk55.

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12 years 5 months ago #11694 by jtallen83
Replied by jtallen83 on topic Re: The Tale of a Rifle and a Load
Stories like this make me think twice about investing my time and money in reloading. With my poor old eyes I don't stand a chance getting optimum accuracy anyway! Now if I had one of those Wilson rifles.... :whistle:
Thanks as always for the education!

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12 years 5 months ago #11697 by zfk55
Replied by zfk55 on topic Re: The Tale of a Rifle and a Load
Nah. Stick with it. Dad is 70 now and he's still an avid reloader. Young eyes always persue the relatively pointless. Who cares if you can shoot sub-moa or 4moa at a target or game (all kinds) Both will do the job and it keeps you sharp, and it keeps old hands busy and away from the young skirts! :lol:

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12 years 4 months ago #11917 by zfk55
Replied by zfk55 on topic Re: The Tale of a Rifle and a Load
The odd thing was that for a period of time our logbooks showed a whole string of sub-moa groups for the rifle running for a week or more. When it changed again I actually had an upset stomach. Too intense about that elusive tight group I guess. I was reminded that in that time period I had not been using my prescription shooting glasses. That should have told me something but I was looking in the wrong places for an answer. How could a prescription giving me 20/20 be a problem, eh? :S

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