quote:

Originally posted by fritz:
5/13/18 -- As I suspected from a couple prior sessions, the 2-10X scope I purchased in December for my 16" barrel AR-15 won't hold zero and has tracking issues. Crap. From one session to another, zero can change 3-4 MOA. Between tall targets, dialing elevation & windage to max and back again, I experienced a 5 MOA downward shift after roughly 100 rounds in 3-round groups.

5/14/18 -- I wasn't ready to send the scope back to the factory. So I put my NF 2.5-10x on the upper. Initially this combo shot a little better. Then I started dialing elevation a lot, in combination of getting the barrel pretty warm. Dagnabbit, the wandering zero resurfaced. I noticed that the gas block seems to be moving (rotating) in relation to the opening in the 12 o'clock portion of the rail that allows clearance for the gas block. When the barrel was pretty warm, the gas block touched the rail. With the barrel totally cold after being the safe a couple days, the gas block no longer touches the rail.

The problem may have been with the upper, not the scopes. I should be able to confirm over the weekend.

After discussing the issues with my preferred 'smith, he took this 16" Wilson Combat upper back to the shop and gave it a careful inspection. His analysis:
- The barrel nut was fairly tight, but not completely so. My 'smith torqued it down to spec and stated there shouldn't be issues going forward. He said the 'smith who replaced the barrel may not be all that familiar with Wilson ARs.
- There's very little clearance between Wilson's TRIM rail and the gas block. My 'smith did a little milling to open up the clearance, as he suspects bipod pressure and heat from shooting makes the limited clearance a bit too limited.
- With the barrel nut now tight, the handguard shouldn't rotate relative to the gas glock.

I hoped to try the tweaked upper last weekend, while sighting in at the Raton 2-gun match, but ran out of time on the sight-in evening.

The goal for the weekend is to chrono my primary ammo types, find a good zero, perform tall target tests to confirm that optics are good, and see how the upper holds vertical at 400-500 yards.

I have an Origin action on preorder and have started looking at barrels, boy it looks easy to change out with an action and barrel wrench. I don't have much time shooting longer range, and I wonder if I should get a .223 bolt head and start with a .223 barrel. You can get Hornady American Gunner 6.5cm for 80 cents a round, so I'm not sure the economics are there for practice ammo. What do you guys think?

quote:

Originally posted by Voshterkoff:
I have an Origin action on preorder and have started looking at barrels, boy it looks easy to change out with an action and barrel wrench. I don't have much time shooting longer range, and I wonder if I should get a .223 bolt head and start with a .223 barrel. You can get Hornady American Gunner 6.5cm for 80 cents a round, so I'm not sure the economics are there for practice ammo. What do you guys think?

I'm not familiar with the Origin action. Offgrid has many thousands of rounds on his Bighorn actions -- he may be able to help you. I can state that offgrid's Bighorns shoot really well and they cycle very smoothly.

I am in the slow process of building a 223 precision rifle, as a training option for my larger caliber rifles. Quality 223 ammo can be found for less than 6.5 ammo. Furthermore, a good 223 match round flies a long ways with good accuracy. The downside to 223 bullets is that they show noticeably more wind drift than their 6.5mm counterparts.

quote:

Originally posted by fritz:
The goal for the weekend is to chrono my primary ammo types, find a good zero, perform tall target tests to confirm that optics are good, and see how the upper holds vertical at 400-500 yards.

Somehow, I don't have 100% success rate with goals.

I'm pretty comfy that the tweaked 16" Wilson upper is now put together correctly. Although I had only limited time with with AR this weekend, I didn't experience its prior issues. No movement of the gas block relative to the rail. No contact between gas block and rail. Accuracy was more consistent across a limited number match-grade ammo lines. But I still need to confirm accuracy across all my match-grade ammo options.

Before the 'smith tightened the barrel nut, I experienced a number of groups with very little vertical dispersion, but with noticeable horizontal variation. I attributed the horizontal to high & variable winds, but it may have been due to the harmonics of gas block contact. 100-yard groups now appear more concentric. Winds were unpleasant while shooting, so I didn't stretch out to longer distances. Testing a limited number of ammo options for group size and muzzle velocity was enough for the day.

One of my original concerns with this upper was the optic -- a Vortex PST Gen II 2-10x ffp. Initially, I was concerned that wonkiness in accuracy and POI was due to the scope. I'm glad I didn't blame the scope from the start of this journey. But I think I have found one issue with the scope.

First, the good news on the Vortex 2-10x.
- Glass is really clear.
- Parallax function is great.
- Reticle is useful and OK -- but I like the MOA reticle from Nightforce better
- Zero stop function is relatively easy to set
- Turret feel is decent.
- It's one of the few FFP 2-10x optics on the market. Burris is one other.
- Turret elevation tracks with reticle elevation. i.e. either holding or dialing elevation works....within reasonable values....

I think I can live with the one downside of this scope. When I spin the elevation turret all the way to the top, then back to zero, then back to the top, then back to zero -- the zero elevation changes by 1 to 2 MOA. This shouldn't happen with a properly designed scope, but it does with this one. So....I just won't dial up 65-70-ish MOA in elevation anymore and bang up against its maximum value anymore. Which is more than 2 revolutions on the elevation turret -- 25 MOA per rev. I doubt I will ever use more than rotation on the turret anyway, so it's just something to remember. When I kept dialing/holding under 32 MOA, tracking was accurate and repeatable.

Nightforce may one day distribute a 2-10x (-ish) ffp scope -- possibly in their NSX line, but could be SHV or ATACR. One NF rep told me 2-10x ffp ain't happnin', but another rep had that look..... Until then, I hope my Vortex scope continues to play nicely with my Wilson 16" upper.

I shot my 18" barrel Wilson AR-15 in the Nightforce precision tactical 2-gun match last month. I shot the Wilson with stunning accuracy for the first day, but I just didn't seem myself on the second day. I shot the AR like dog-doo on a stage which required somewhat wobbly spools for support. I figured it was my technique, but I shot lights out from the spools with the precision bolt action rifle, after switching from the AR.

On the next stage, the direct thread suppressor become slightly loose -- causing accuracy to totally suck until I tightened the can in mid-stage. Gotta love heat resistant can covers.

But I still wasn't as accurate as I expected on the next stage.....hmmm

When I cleaned the AR I felt a slight constriction with patches early in the bore. And more carbon on the patches than normal. I shot the Wilson the following weekend briefly and accuracy was really bad. As in match ammo shooting worse than ball ammo. I began to wonder if the barrel was toast.

So I put a number of Slip Carbon Killer patches down the bore, even leaving them in the beginning of the bore for a few hours. More patches, then copper and plastic brushes. The constriction went away, as did carbon fouling on patches.

I shot the 18" Wilson again today. For whatever reason, I had to re-zero. I shot the rifle's favorite round -- Hornady 75 grain HPBT match. Initial 3-round groups to zero were printing at about .5" at 100 yards. A good sign, for sure. To confirm zero I shot a 5-round group of .61" at 100 yards, with all the variation being horizontal. Woohoo! Given that I was experiencing gusty winds from my 3 o'clock while shooting the group, wind drift variation could have added .1" or .2" to the group's size. Serious woohoo!

The barrel is still good. When it eventually does crap out, I will replace it with a Krieger or Bartlein.

In other words, I've experienced my first carbon ring in a AR-15 and learned how badly it can screw up accuracy. I suspect the stages where I had to hose close-ish paper targets with cheap FMJ ammo contributed to excessive carbon fouling. Lesson learned, and hopefully will be remembered.

I shot my first competition last weekend in the 600 yard F-Open class. it was a small-ish club event where all 24 participants shot, spotted hits (scored) and pulled targets. It was a great learning experience. In some ways it was a lot easier than I imagined and in others, a lot harder than I imagined. it is easy to shoot a 9, harder to shoot a 10 and surprisingly difficult to shoot an X. Wind was dead calm in the morning but it did get gusty by the last round. I brought way too much gear, dressed completely wrong in long pants and long sleeves and used ammo out of my reload boxes in a very inefficient way. I only brought my small tripod to use with my spotting scope necessitating laying prone for 20 minutes spotting for another shooter. That caused extra fatigue in my shoulders. Won’t make that mistake again. My aggregate score was 574 - 11X. I did shoot one 8.

Here is a quick analysis of shots:
2% were > 1.5 MOA but < 2 (8 ring)
37% were > 1 but < 1.5 (9 ring)
43% were < 1 but > .5 (10 ring)
18% < .5 MOA ( X ring)

I made the decision to shoot the match 6 days before the event. I took a few hours off of work to go verify loads still worked as I couldn’t shoot suppressed. All of my load development is done suppressed and until the match it is the only way I shoot. I shot my Tikka T3X TAC A1 in 6.5 Creedmoor with a Harris bipod and rear bag. This was also the same weekend we took our oldest son to his new college. Preparing for the match was a real grind due to the short time to prepare, having to verify/reset zero w/o the suppressor and diminished sleep due to travel.

One funny occurrence: I was calm, relaxed and ready to shoot when it became my turn. I spotted first and shot in the second round. As soon as I got down into prone and behind the gun I realized this was a real competition and I didn’t want to screw up. My heart began to pound and the first sighter shots were timed between big heartbeats. I did eventually calm down and was fine in subsequent rounds.

All in all a very fun day and lots of points of learning.

Henryrifle

For much of this year I've worked to find the best factory ammo for two new 16" barrel 1/8 twist barrels and a low mileage 14.5" 1/7 barrel. All barrels are chambered in 5.56. I prefer 223 ammo, but have tried some 5.56 ammo.

My first AR-15 barrel was 16" 1/9 twist. It had a strong preference for FGMM 69 (and other 69 SMK loads) and Hornady 55 Vmax, shooting both right around 1 MOA with a 1-5x scope. In hot weather it sometimes liked FGMM 77, but never really cared for Hornady 75 HPBT. When this barrel no long held vertical at 400 yards with FGMM 69, I knew it was time to be retired as a tomato stake.

I have two 16" 1/8 barrels -- a replacement for the toasted 1/9 twist, and second upper. Even with the faster twist, one barrel doesn't care for any bullet over 69 grains.

The other 1/8 shoots 75 HPBT and 73 ELD-M well at 100 yards -- equal or better than SMK 69. But at 300 and 400 yards, the SMK 69 shows better accuracy than the 75 and 73 grain bullets. Both of the 1/8 barrels think 55 Vmax is the cat's meow.

My 14.5 1/7 barrel just sucks canal water with 73, 75, and 77 grain loads. It shoots 55 Vmax pretty well, but not up to standards I'm used to. Fortunately this barrel shoots quite nicely with 69 SMK -- Federal, Aussie Outback, and Copper Creek. It is the most picky barrel I've owned. Fortunately, I won it in a competition. I'll shoot the crap out of it, then hopefully get a different brand barrel down the road. FWIW, it's my only piston upper. Unknown if that's part of its accuracy issues with many bullets.

It comes down to realizing that my 14" and 16" barrels really have two common ammo themes -- Federal GMM 69 and Hornady 55 Vmax. I'm in the last stages of reducing my ammo inventory to these loads for these barrels.

My longer barrel ARs also shoot FGMM 69 and Vmax 55 well, so no issues here. However, my longer barrels do a little better at distance with heavier bullets. The 18" 1/7, the 20" 1/7.7, and the 24" 1/8 all like Hornady 75 HPBT.

The 20" barrel (my only true 223 chamber) does best with 73 ELD-M at all distances, and thus it's my go-to rifle when bolt-action-class accuracy is helpful from an AR-15.

During the Obummer administration I may have had up to 30 different loads in inventory. There were times when a good deal on even a few boxes of ammo was the ticket, especially when normal distribution channels had bare shelves. Soon, I'll be down to 5 loads when accuracy is the goal, plus American Eagle 55 FMJ when competitions include paper IPSC targets at relatively close distances.

The search for accurate ammo has been an interesting journey, although I tried way too many different loads over the years.

I was having a tough afternoon testing 300blk ammo for accuracy at 100 yards. Granted the blackout rifle isn't the ultimate for accuracy -- 11" barrel, 1-5x glass, and pretty standard collapsible buttstock. Winds of 6-12 mph from my 2 o'clock wasn't helping. After a few groups of more vertical variation than normal while using various supersonic ammo, it was time to compare results from my best 223 AR-15.

The 223 produced a 5-round group of .2" vertical and .6" horizontal variation. Wind speed changes probably accounted for .3" of the horizontal variation. OK, I'm shooting just fine with heavy rifle with a PRS stock -- maybe I just can't shoot an SBR today.

But I think ammo is part of the inaccuracy issue. I think I've finally found some 300blk ammo that shoots accurately in my SBR. Honestly, I didn't think this would be such a challenge from a quality SBR upper. I'll share my ammo journey once I have the time for a write up.

I shot the Team Safari match a few weeks ago with offgrid. Great match, we improved over last year, and now I'm starting to think about next year's matches.

The individual Steel Safari in some ways is harder than the 2-man Team Safari -- equipment for gun support being one area. Many stages cannot be shot from prone, so a sturdy tripod is recommended. Some shooters do most of their stages from standing tripod positions, sometimes with rear sticks. But time is always a factor in the Safari matches.

One of the better shooters around here uses a single trigger stick for rear support. I tried this last week, first with a heavy AR-15 before moving up to my bolt action.



My targets were plates at 250 and 370 yards, in winds of 5-9 mph from my 4-5 o'clock, using my last few boxes of Frontier 55 grain HP match ammo. The first plate at 250 yards didn't go all that well. I struggled to set up quickly. I was fairly stable vertically, but between the wind and side-to-side wobble of the single rear stick, the results weren't that good. OK, set up again, dry fire, set up again, dry fire.

On to 370 yards. Still a lot of side to side wobble, but vertical still good.



Yep, wind and wobble makes for lateral dispersion. But vertical was good. Left plate 2-1/2" vertical and 7" horizontal. Center plate 2-3/8" vertical and 7-1/4" horizontal. Right plate 2-3/4" vertical and 7-1/4" horizontal. Interestingly, that's holding vertical to about 2/3 MOA. That Frontier ammo really was only 1.5 MOA-ish for me at 100 yards from prone. I noticed my POI was a little high on the plate compared to prone, so something must be wonky with my technique.

After walking out to repaint the targets, I figured I should re-shoot them prone to see how the Frontier ammo did. In that short time, a cold front arrived, wind increased to 10-15 mph from my 4-5 o'clock, temperature dropped 8 degrees -- now in the low 40's. From prone my targets had had 3-1/4" vertical, then 2-1/2" vertical, then 2-1/4" vertical -- all with about 4" of horizontal dispersion.

So...it appears I can hold vertical with this method. I need more practice to get faster with setup and movement between targets, and I need to become more stable horizontally.

My Bighorn Origin action is on the way. Now to decide on a trigger.

Anyone using an MPA chassis? I put a Bighorn TL3 into one and am finding the magazines seat too low to feed properly.

quote:

Originally posted by buddy357:
Anyone using an MPA chassis? I put a Bighorn TL3 into one and am finding the magazines seat too low to feed properly.

Is the chassis cut specifically for the TL3?

What mags?

How much vertical play with mag?

So far with a modded pmag, an aics and an accurate mag (dssf). No vertical play. Going to have to find out if I got the wrong model somehow, that had not crossed my mind. Thanks offgrid.

quote:

Originally posted by buddy357:
So far with a modded pmag, an aics and an accurate mag (dssf). No vertical play. Going to have to find out if I got the wrong model somehow, that had not crossed my mind. Thanks offgrid.

Post a picture showing the rear tang in the chassis.

I never noticed,maybe the tang isn’t seating well. I have verified it’s supposed to be for Remington 700 and clones, supposedly the mpa inlet for the TL3 is the Remington inlet with no changes. But I don’t know how to tell by looking if that’s correct.

Similar fit I see on other MPA chassis. Only chassis I know of that will be a 100% 1-1 fit is the XLR.

Suggest to focus on just one brand mag. I have 10's of thousands of rounds on AICS mags, 100% feed on several calibers with some minor feed lip bending.

Hard to tell from the angle of your first picture...it appears the case needs to be presented a little higher, bullet tip angled up a little more. Easy fix! Guessing the snap cap will behave a little different than a dummy round? Do all this with dummy rounds. MPA sells a feed lip bender. I made my own, simple 1/2x1 aluminum bar with slot cut on a band saw. Could also use a small Crescent wrench, taped up lineman's pliers.... Start at the back with a single round in the mag. Bend the lips up so that the bottom of the primer pocket is even with the rear of mag, just expose the entire primer pocket. Try to bend from the lowest point of the lips where the lips meet the side of the mag. Flare the lips toward the front so the round is slightly angled up. Rear gap between the lips will be slight narrower then the front. Make sure the feed lips are not curved/bowed in/out from the rear to the front. Push the single dummy round forward to check the straightness of the lips compared to the case, want complete contact. I have six mags, not bent exactly the same, they'll tolerate some wiggle and still feed 100%. Hope that helps you.

Thanks Offgrid, I’ll try that. Do you recommend the aics mags? I was going to try accurate mags because the 10 rounders are shorter, but if the aics ones are better I’ll stick with them.

I’m gonna make up a dummy round but the magazine I have doesn’t seem to need it. I tossed in a round to see how far off and it doesn’t seem to be. Then I pulled that round out because I didn’t want live rounds nearby once I started fiddling around with the rifle. Didn’t want to risk it.

With closer inspection it seems the magazine is hitting the front feed lips of the action about 1mm before the magazine locks in. Maybe the front is preventing further upward motion to allow it high enough. I saw a few folks had to add length to the magazine release but with th action stopping motion of the magazine I doubt it’d help.

Recommend AICS mags, will fit your action better. Like I said above have 10's of thousands of rounds on them, they work. Never had a problem with the length. If your action is AW cut, could try those. My actions are AW cut, AW mags do feed like butter. BUT, aggressively inserting mags under a clock I've popped the first round out, double feed.... Also for whatever reason the AW mags are not as consistent in dimension as the AICS. Mostly use AICS mags in matches. Occasionally use a AW mag because I can stuff 11 Dasher rounds in them.

The weekend weather around here hasn't been very conducive to shooting for a few weeks. Yesterday was predicted to be between minor snow storms so it became a shooting day. But first, ranch duties called.:

Yucca removal never seems to cease, even in winter months. Given that the temps started in the 20's -- with wind -- a little physical labor got the blood flowing.

I continue to work on shooting from a standing tripod position, with a single-pole trigger stick for rear support. The first target went OK...

420 yards, 9 hits out of 10 -- 3.5" vertical & 7.25" horizontal -- FGMM 77. Vertical variation of about .8 MOA.
38 degrees, winds at me of 10-15 mph from 8-9 o'clock
effective wind holds of 12-18 mph at the target -- wind speed higher down range.

Unfortunately the winds picked up and the temps dropped to 32 F. Drift at the target increased to 20-25 mph, with an occasional WTF 30 mph drift. Lots of wobble from a standing position; lots of lateral bullet drift.

I struggled with a POI from the standing tripod position that was consistently high -- between 1 and 1.5 MOA, depending on how I set up for a given magazine of shots. The POI shift was worse for the 300-400 yard targets than for the 200-250 yard targets. Wondering if my POI issues were DOPE or zero issues, I dropped to prone and shot all targets -- elevation was dead on.

So I tried standing tripod without the rear trigger stick, but using a sling on the front of the rifle, pulling downward on the sling and holding it against a forward tripod leg. Voila, POI exactly where it should be for that target distance and Density Altitude.

So then I tried kneeling tripod -- sling on rifle front, pulled down to forward tripod leg with left hand, rear of rifle stabilized by right elbow supported by right thigh. Voila, POI good and lateral wobble significantly reduced.

IMO this means I'm in my comfort zone with the kneeling tripod position, but I need more practice on the standing tripod position.

Although I was dressed pretty warmly, shooting in such conditions wasn't a whole of fun. I only brought leather work gloves that aren't insulated, so my hands were pretty cold. My routine was to sit in the car, load up a magazine of ammo, and drink a little hot chocolate. Then go shoot the magazine. Return to the car, load another mag, drink some more chocolate. Walk down range to spray paint the targets, return to the car, and drink more hot chocolate to warm up.

I decided to call the day quits when a storm cloud blocked the sun, the wind shifted, and the air had the feel and smell that it could start snowing at any moment. While swilling the remaining hot chocolate in the car and pondering tripod technique, I thought of Matt Damon's line in "The Martian" -- I would love to solve this problem right now, but unfortunately, my balls are frozen.