Home Forums Hunting & Shooting AR and Tactical Rifles 24HC MOA All Day Long Challenge

Just for you, BSA. Calipers are bracketing outside-to-outside edges, so remember to subtract bullet diameter.

we hit 100 a few weeks ago south of you unfortunately and I"m stuck in TX at the moment. LOL. Soon to fly north though thankfully.

Subtract bullet diameter is very optimistic - none of your holes will be that big. It's *much* more accurate to measure from the outside of one hole to the inside of the opposite hole.

Probably so, which would explain small discrepancies that can be detected in my caliper photos. Initial measurements as reported in my first post were made outside-to-inside.

I placed the calipers in this manner for photographic purposes because it seemed like it would be easier to discern good caliper placement. No deception intended!

I use the carbon marks left by the bullet as measurement points. Every time I have scrutinized carbon marks, they have been "exactly" bullet diameter. Is this not true in your experience?

caliber size plugs opened my eyes a few times.

Regardless the groups are good. Doesn't matter what a measure says unless you are in a match. LOL.

Okay, here's a new entry...actually the same rifle I put up here on this thread a few weeks ago, but this time I've followed the rules to the letter (at least I think I did) to satisfy our stickler for rules, Mr. BSA himself. Results were actually a little better this time.

First, the range...this is at North Texas Shooters Association located a few miles north of Denton. Conditions were excellent.



Here's my rig. I've described it before in detail (it has a bit of a history as a problem rifle), but in general it's a Model 70 HV on its second barrel (an OEM takeoff from another M70 purchased from Gun Parts Corp. a few years ago). I think I put a Rifle Basix trigger in this one about three years ago but I'd have to look through a large pile of receipts to verify that. It sits in an HS Precision stock. The scope is a Burris Fullfield E1 6.5-20x50 supported by Leupold Dual Dovetail bases and rings.



After I completed the first group, I thought I'd try to take this shot. It worked okay, but it can be done better. Just did it for the hell of it. I have several targets posted at the time, but the one I shot is the upper right-hand target. If you look closely you can just make out the first group.



...and here are my results.



My 0.88" average works out to be about 0.84 MOA. This is the second consecutive successful attempt to do this with this rifle and load, so I feel comfortable making the claim that it will shoot MOA all day long.


Did I earn your seal of approval, BSA?

Yeah, that's the reason I always measure like you suggest. Shaking my head here, why guys just don't do it that way. Its easy.. Some guys like complicating chidt though..:


Sometimes I even measure from grease ring to grease ring, for a little more accurate measuring. In the above pic, you can see I could have scooted my caliper in just a hair more (bringing my sub moa score down a bit), but hey its close and much closer than subtracting the bullet diameter from an outside to outside measure... Here's another one:


I think I just called it .600"

Looks great. I give you an A+ for sure.. Love the rifle and like the fact you are using a Burris rifle scope in the DD's. I like that you are rocking the Winchester model 70 and making it shoot that well...

Now that I've examined the question a little more carefully, I can see that you are right.

I have a number of bragging targets cut out and pinned to a bulletin board, and I took a closer look at them. I had always assumed and believed that the carbon marks made by a bullet passing through a paper target were exactly equal to bullet diameter. I took some of these target cutouts down and measured them. The carbon marks appear to be just a little less than bullet diameter...not enough to make a huge difference but enough to make the outside-to-outside measurement minus bullet diameter a little optimistic. The inside-to-outside measurement would be much closer to exact.









Thanks.

And about that scope...(*ahem*). I had a VX-3 or 3i 6.5-20x40 on the rifle since I acquired it six or seven years ago. I pretty much lost confidence in the VX-3 and VX-3i last Fall and peddled every single one of them I had. I still have a VX-II on a muzzle loader and four VX-5s on some other Model 70s and a sweet little Model Seven in 6mm Remington ( I LOVE those scopes and hope they never give me reason to doubt, but I ain't married to 'em). But now I am wondering if the Leupold that used to sit on the rifle was a part of the problem, and now it would be someone else's problem. I'd rather think not. I have to say that the load I'm using in the Model 70 now is not the same one I was using before I made the change over to Burris and Sightron, so the problem could have been either the loads or the scope. I think I still have a few rounds of the old load, so I need to wring them out again and see what's what.

Old load was a 50-grain V-Max over 25.75 grains of Benchmark. New load is a 50-grain Ballistic Tip over 25.6 grains of X-Terminator.

Yeah, I gave up on Leupold when the last one failed me. I said never again!!!!! The nice thing about 223 rem is they are easy to get to shoot. The same goes for every 22-250 ive seen. That cartridge always seems to impress me. It reminds me of a little creedmoor.

Yeah, it matters a lot more with a ~ <1/2" group than it does with a 2"+ group!

This isn't exactly following the OP's format, but I'll post anyway. Conventional 500 yard, 20 shot high power string with 2 sighters (foulers in this case).

First 10 shots 1.197 MOA 99-7X
Shots 11-20 1.462 MOA 100-4x

AVE. 1.330 MOA Total 199-11x

Prone with sling, iron sights M70 Winchester .308, Berger 155.5s

Silver Mountain Solo E target.

Eyes pretty tired for last shots!

Dang, Mike...that is some pretty fine shooting. Made my eyes tired just reading about it!

Groups are sometimes hard to measure...


And yes, I totally agree with the statement that subtracting the bullet diameter from the outside to outside measurement is very "optimistic". However, guys started doing that right from the get go in this thread. I overlooked it, as this challenge isn't like a world championship or anything, it was just meant to be fun and maybe a little bragging right on your rifles. I think I've brought just about every rifle I own and entered them into the challenge. For the most part, most of my rifles have proven themselves to me as sub moa shooters. The funny thing is some of my last targets will show you guys what Tyrone, myself, probably rost, and some other guys that shoot competitively are talking about with the way you are measuring to be off just a wee bit.

Generally I just plop the damn caliper where I think the center of the hole is, and yes, that is even closer to an actual measurement than outside to outside and subtracting bullet diameter. Like these for example:

Yes, that is even closer to actual group size than subtracting bullet diameter.
To show you guys what Tyrone is talking about, lets measure some easy 3 shot group targets, because my 10 shot groups are always hard to measure...

Example 1: This is a .443" 3 shot group:


Now, when you measure outside to outside and subtract the bullet diameter, the number shrinks:

Surprisingly it shrinks quite a bit: to .407"

Example 2: Here's another 3 shot group from my Noveske. It measures .502" inside to outside, which is actual group size:


But when you lay the caliper down and measure out to out, then subtract the .224", it is surprisingly smaller:

Now, that is saying .451".

This is why I always measure inside to outside. It's a more accurate way to measure group size. If I can't measure that way, plop it down in the center of the hole. Its still more accurate than out to out measure...:

Here's a target that would be top score here, had I measured erroneously....:


Prime example:



Had I measured that way, the over all score (2 10 shot groups) would have been .497 MOA. However, In my own clear judgment, I would not be able to do that...

Hell, my Tikka T3 22-250 would be in the top 3 and kick John Hondo off of his #2 spot, and that's a brand new rifle to me. That adjusted score would be .554 moa... Just sayin

I remember a 1SG talking how he got his Soldiers to become a better team/cohesive group and it was by getting them to hate him. Another Sr. NCO said 1SG that’s a way, but not the right way..

Nice shooting!

There's always a right way and wrong way. Sometimes an accepted way doesn't always mean it is right. If it does, I'm changing my fu cking scores.. and you mo fo's can eat chidt...

Some do it the way you and t dog do it, some do it the way I do it, which I read about and seems the most common method and others when measuring the two furthest holes split them in half.. like our match director says before the start of every shoot. Gentleman we are here to have fun and no world records will be set here today.. ie just have fun..

With that no world records will be set here.. and I call bull chit on your 3 shot group you posted lol

Ha ha.. That Noveske shoots awesome 3 shot groups buddy. Its also the only rifle I have not been able to get into the sub moa category in the black rifle challenge. I've said it many many times that it is my least accurate AR15 and that is the truth. One of the reasons I threw on those back up irons and shoot the black rifle event with the irons sights. The funny thing there, when I'm shooting with irons, it will often times shoot 1/2" 3 shot and sometimes 1/2" 4 shot groups with irons:

This is a 4 shot group with iron sights with that rifle..