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Grenadier
06-10-2017, 01:42 AM
Tim Shufflin converted my M1 Garand into his mini-G configuration. The original rifle was handed down to me. It had seen a lot of use and it was not a very good shooter. So, I wasn't surprised when Tim informed me the original barrel was shot out. Since a new barrel was needed I thought it would be nice to convert to .308. The new barrel finish should match the rest of the rifle so I ordered a complete parkerizing job. And, with everything new or being made like-new, I felt compelled to order a new stock.

I shipped the original rifle and a brand new Holbrook Device to Tim. I ordered a finger groove stock from Stock Emporium and had that shipped directly to TIm. Tim added a new barrel and an adjustable gas plug. He installed the barrel, parkerized all the metal, and put everything together in the new stock. You can see the results below. I photographed it next to a Thai Border Police M1 Carbine for comparison. I was, and remain, very pleased.

http://farm5.staticflickr.com/4112/34886541234_38ed881e5e_b.jpg


AMMUNITION

Tim informed me that the rifle was adjusted to shoot M80 147gr ball ammunition. I had no interest in shooting that. Anyway, I didn't have any on hand. However, I did have a few boxes of M118 and M118 LR, 173gr military Match ammo. So, with great hopes I took that out to give the rifle a go.

The results were dismal. It quickly became apparent that the ammunition, both versions, wasn't getting enough velocity in the 16" barrel of the mini-G to rotate quickly enough to stabilize. I was seeing big groups and lots of key holing. To make matters worse, no matter how I adjusted the gas plug I couldn't get the rifle to function reliably. I think the cartridges and loads were too high and beyond the capabilities of the system to properly conform to. M118 /M118 LR earned a big NO-GO in my rifle.

I decided to purchase some Fiocchi ammunition topped with 165gr Sierra Gameking bullets. The bullets are shorter than the 173gr M118 bullets. That, I guessed, coupled with the additional velocity gained by shooting the lighter bullet might generate enough spin to stabilize the bullets. The 165gr load is also closer to the M80 load and I expected it to improve feeding and functioning.

I tried the ammo at the range and things couldn't have worked out better. It took some rounds to dial in the gas plug but it now performs reliably. One bug added benefit to this Fiocchi load is the excellent for hunting use Gameking bullet.

Here is Sierra's description of the bullets:
For rifles in 30 caliber, this 165 grain #2140 Hollow Point Boat Tail bullet, which is patterned after the world-famous 168 grain MatchKing bullet, was designed for shooters who desire a hunting version of that famous MatchKing. It is slightly "harder" than its 165 grain Spitzer Boat Tail counterpart and will give superior penetration and good expansion on medium game with excellent accuracy.

I'm getting a mean muzzle velocity of 2597 fps from my mini-G. That works out to:

Optimum sight-in range = 194 Yds.
Maximum ordinate above LOS is 2" at that range of 117 Yds.
Maximum point blank range (+/- 2" from LOS) = 224 Yds.


However, it works out that a 50 yard zero will also result in a 150 yard zero. The first distance is where the bullet crosses the line of sight on the way up and the second distance is where the bullet crosses the line of sight on the way down. I can zero for 150 yards on my 50 yard range. That was just too convenient to ignore. It also has a very flat trajectory. The bullet never rises more than .8" above the line of sight and is only 1.1" low at 175 yards, 2" low at 190 yards, and 2.7" low at 200 yards - great for hunting.

Once I settled on the Fiocchi 165gr Sierra ammunition I decided to focus on zeroing and accuracy.


SIGHTS

I am more than a little accustomed to military iron sights. I had no trouble getting a zero with the issue sights but groups were not as tight as I expected. I was averaging about 3-1/2" at 50 yards. That would be twice that at 100 yards and four times that at 200 yards. That's not good enough even for deer hunting. There were two issues holding me back from getting tighter groups. First, I developed a vitreous separation in my right eye last year. It has left me with a large, permanently attached floater that makes it difficult to focus on the front sight. There is no way I can compensate for this with iron sights. Second, the back of the Garand receiver beats me in the upper lip. I've always experienced that with Garands. Every time I fired a Garand in a match my upper lip would be swollen and bloody by the 20th round or so. I could add a pad to the buttstock to get more length of pull but I don't like doing that on military rifles. So, for me, the issue sights were not the best option.

I decided to add a Burris Fastfire III. I received one as a rebate promotion after I purchased a Burris AR sight. All I needed was a mount. I located a company that makes those and soon had everything together without difficulty.

Here is a picture of the setup:

http://farm5.staticflickr.com/4067/34886588044_667ded962a_c.jpg
http://farm5.staticflickr.com/4283/35340745420_acc4feaa0e_c.jpg

Grenadier
06-11-2017, 12:08 AM
Continued.......

The Fastfire 3 unit worked great at 25 yards but it was difficult to use at 50 yards. At the longer range I was having problems with parallax. I was looking for hunting accuracy but Fastfire was giving me fast target acquisition with only CQB accuracy. I could align the dot with the front sight and vertical line on the back of the Fastfire to reduce side-to-side parallax but I still had problems with vertical parallax.

Here you can see how the Fastfire suffers from parallax. When the dot, front sight, and rear white line are lined up it shoots true. When you move your head a little bit one way or the other the dot moves from side to side.

http://farm5.staticflickr.com/4081/34886561954_4db90bb619_m.jpg

The target below is typical of what was happening. This 50 yard group measures 0.5" x 1.6". That would be 1" X 3-1/4" at 100 yards, 2" X 6-1/2" at 200. That's much better than I got with the iron sights but I knew the rifle would shoot better if I could address the vertical stringing.

http://farm5.staticflickr.com/4239/35340746050_42898db401_m.jpg

That grouping is okay for close, tree stand, and blind hunting but it isn't good for stalking or hunting in open terrain.

Reluctantly, I decided I needed to scope the mini-G to eek out the best accuracy. I say reluctantly because I like being able to shove a clip of eight rounds into the magazine. As mentioned in the start of this post, I had a Holbrook device installed. That keeps the clip in place until you manually press the clip release button. It prevents the automatic ejection of the clip after all rounds are fired. It also allows individual rounds to be loaded directly into the clip while it is still in the magazine. This last feature means a scope can be mounted directly over the center of the action and rounds can be individually loaded just like is done with a typical bolt action rifle.

I purchased a CASM mount from a Canadian firm. It replaces the rear sight and requires no drilling or tapping. I installed the mount and secured a Leupold 1-4X Hog scope to it. I really like the Pig-Plex reticles in the HOG line.

http://farm5.staticflickr.com/4130/35596573881_c990537522_c.jpg

I went back to the range, zeroed the rifle, and proceeded to shoot a couple of groups like this one. It's 8-shots and measures 1/4" X 7/8" to the centers:

http://farm5.staticflickr.com/4280/34886563174_a0563ec465_m.jpg

If I can stop the vertical stringing I will be shooting better than 1 MOA! Of course that's an IF and at 100 yards winds and other factors will have a meaningful effect so that may be optimistic. But this gives me an idea of what the rifle is capable of in more ideal conditions.

I have come to the conclusion that the problem is my inability to maintain a consistent cheek weld. Shooting either the Fastfire or a scope requires raising the head from the stock. The parallax of the Fastfire exacerbated the problem but it still exists when shooting with a scope.

I verified the fix by shoving some foam under the butt pouch (as can be seen in the photo above). Raising the comb will do the trick but I need to get the comb raised with something more permanent and I need more ammunition to see what the rifle is really capable of. Once I get that done I'll post an update. Then there's the cow elk tag I drew for Colorado this year........

timshufflin
06-11-2017, 09:56 PM
Wow, now you have done some work here. I just shoot 180 grain .308 remington with open sights and it seems to kill stuff pretty good out to 300 yards. Someday, I'd love to play with all the loads out there like you have, great job. I've most always found heavier loads to do best for me.

Grenadier
06-11-2017, 10:17 PM
Wow, now you have done some work here. I just shoot 180 grain .308 remington with open sights and it seems to kill stuff pretty good out to 300 yards. Someday, I'd love to play with all the loads out there like you have, great job. I've most always found heavier loads to do best for me.I didn't try a lot of ammo. I figured the M118 was giving me trouble because the bullets were long and the cartridges pretty stout. I went to the Fiocchi because it was a step down from there. If the Fiocchi didn't work out as well as it did I would have tried something else. I am sure there is a lot of ammo that would perform excellent in these rifles. But as I mentioned above, being able to zero at 50 yards for a 150 yard zero is a really big plus for me.

timshufflin
06-12-2017, 03:58 PM
I know you didn't try a lot of ammo. I'm the one who wants to try a lot of ammo :D

Grenadier
06-12-2017, 04:31 PM
Thanks, Tim. All fixed up now, I see.

timshufflin
06-12-2017, 06:20 PM
I had no idea that they weren't visible. I don't have you as a moderated member.

PeteAR10
06-19-2017, 09:25 PM
Great write up with excellent information - Thanks. Beautiful rifle too. I had almost the identical rifle built, and I too am very happy with it. I am also struggling with some issues with regard to vision, and have given a lot of thought to scoping it, but really would prefer not to if possible. I just ordered a micro red dot and mount, but have yet to receive them. I'm hoping they will be the answer for me. I went with the Leupold, so I don't know if that will make any difference with the parallax you experienced or not, can't wait to find out though. For me the rifle is mostly for plinking, and shooting pigs at 200 yards or less.

JGW
06-24-2017, 07:55 PM
Grenadier - Did you consider the Ultimak rail and scout Scope? That's what I expect / plan for a Tim to do with my conversion. If you did consider same, and decided against it, what were the deciding factors for you?

Greg

Grenadier
06-27-2017, 05:43 PM
I did consider it. I think that's a great setup. However, I wanted to have the added weight of scope and mount rearward rather than forward. I also prefer the larger field of view of a standard scope compared to the narrow field of view of a scout scope. For me the gain was portability, handling, and shootability. But to get those gains I gave up being able to load via clips. I am going to use this for hunting and not things like 3-gun or home defense so loading the magazine one-by-one doesn't bother me.