Stoopid, stoopid me! Argh.

[AZRedhawk44]

I found a used CMP-style float tube last weekend for $50.  And I bought it.  And I installed it on my 1:9 twist Del-ton AR that I've been using in my High Power odyssey.

And I went to the range today to check it out.

My shots are all now about 20-25 MOA left.

At 200 yards, I'm off paper unless I crank the sight all the way to the right.  Then I'm in the 8 ring of an "SR" target, out at 9 o'clock.  Not good enough.  Sight picture is noticeably corrupted... rear sight is way too close to the edge of the carry handle and I feel like the rifle is somehow twisted or aligned incorrectly.

Elevation is fine, dead-nuts-on.  Windage is all screwed up though.


Big problem (and I KNEW it before undertaking the project!): I have a 3-day long match on Friday/Sat/Sun, the AZ NRA state championships.  I've been shooting AR for the last year.

I have my M14 in the safe.  I have ammo for it.  It's sighted in.  I trust it for zombies or an elk hunt.  I can go run it, so I'm not so far SOL that I can't shoot this weekend.

But, I've really been enamored of the AR's design in regards to the standing and seated positions.  That high sight plane is really nice for standing work.  And I really like reversing my forward hand grip and adjusting NPOA around the delta ring to drift the front sight onto target.  The geometry of the M14 doesn't allow for that.  I may end up using a 10rd mag and resting the mag on my forward support hand rather than the stock on it.

I do shoot the M14 better prone (or I did back when I was shooting both rifles routinely...), and I bounce back to natural point of aim better on mag changes with the M14.  I have a hard time as a southpaw with mag changes on the AR on the rapid seated and rapid prone stages.  But I'm fairly worried about standing with the M14.

Funny thing is... I've been dry-firing with the M14 tonight after this botched episode of WECSOG smithing, and I've noticed that the M14 is now CONSIDERABLY lighter than my AR (with lead weights in its *expletive deleted*ss).  That cracks me up.


Sigh.

It'll be nice to have that White Oak arrive.  Only 2.5 more months, according to the original estimate.

I'll tear the AR apart again after this weekend and get it squared away, somehow.  Can't go back to non-floated because I had to cut off the sling swivel mount on the front sight base, so I have to somehow get this system to work.  I think the problem is with front sight base alignment.  Not sure how I screwed that up, but I must have somehow.  Front sight too far right, bullet goes too far left.  Anyone got any pointers for how to adjust a pinned front sight (no fancy screws here, this is a cheapo pinned setup).

[Fly320s]

Is the front sight canted?  Is it bent, or can it be bent to work better?

Just make sure.... you're not using the protective wing as the front sight, are you?  Some people have done that.

[AZRedhawk44]

Is the front sight canted?  Is it bent, or can it be bent to work better?

Just make sure.... you're not using the protective wing as the front sight, are you?  Some people have done that.

Lol.... no.

Yeah, I can see where it's canted now.

Not sure how that's even possible.  There's two channels under the barrel where the front sight pins belong.  Not exactly a lot of options for alignment.  I put the pins in opposite direction from how I drove them out after inspecting for a larger head on one side, and I measured the pins for evidence of taper afterwards.  Both pins were the same diameter at either side according to my dial caliper.  I am afraid that when I drive them out, I'm not going to like what I see.  Probably buggered the holes up somehow, which then means I have effectively ruined the barrel from a service rifle perspective.  Yeah, I can put a different gas port with no front sight on it and mount it to a flat-top receiver, making a 1:9 twist scoped AR rifle... but I don't much want that.  I'll try to fix it... but when I put the FSB on this time, I put red locktite on the barrel between the FSB and barrel.  Probably got into the pin channels as well from the pressure.  That thing is going to be a biatch to remove next time.

Shooting at the range, it was consistent at least.  I was shooting prone at an SR target at 200 (very easy target for prone) but the group was 8-ring 9 o'clock and 1.5MOA with crappy 55gr rapidly produced reloads.  Just took a long while to walk the shots into the paper.  If I can salvage the FSB and barrel and get them well aligned, it'll be a decent rig.

Been dry-firing from standing and seated a bunch tonight, practicing mag changes from seated, etc.  I've got a good system for consistency from standing with the M14 now, I think.  I have a black dot on the wall scaled to 6MOA from 25 feet, been practicing with that.  Using back-pressure against the jacket and listening to my ankles as a substitute for rotating the delta ring on the AR.  From seated, my NPOA is either 100% spot-on... or just awful horrible.  Just a fraction of an inch in geometry change can put the front sight several feet off target even at 25 feet.  Weird how the AR platform makes that so much easier.  Need to figure out the puzzle of this so I can make it repeatable by Saturday (Friday is all prone slowfire at 600 yards... the XTC matches are Sat/Sun).

[Harold Tuttle]

There's a straight edge tool for aligning the fsb

I gather you did not retorque the barel nut and only removed the fsb

[AZRedhawk44]

There's a straight edge tool for aligning the fsb

I gather you did not retorque the barel nut and only removed the fsb

I modified my non-floated A2 upper by removing the existing barrel nut and installing the barrel nut that comes with a CMP-legal free float tube... then installed the float tube onto that.

I've done this once before with this upper, but with a non-CMP legal tube (a hogue aluminum one).  I ended up restoring it back to normal in order to play High Power games, with the intention of eventually getting a CMP-legal float tube.

So I did re-torque the barrel nut.  But it is a new barrel nut.

Got link for fsb alignment tool?

[Harold Tuttle]

i have only seen pictures of ones that bushmaster uses for builds

basically it clamps to the receiver and indexes a straight line down the bore axis

if you re-torqued the barrel nut you could of bent the barrel pin or wallowed the receiver

did you install it to proper torque and then released it 2 times using the proper thread lube?

[Harold Tuttle]

HYG:

http://books.google.com/books?id=6VJvMCNcu5oC&pg=PA68&lpg=PA68&dq=AR15+front+sight+base+%22alignment+gauge%22&source=bl&ots=g9vsFgJAdi&sig=x6QW2AipSFnYReQ6w91q7iDZorI&hl=en&ei=5JDOTsamGYPk0gH4u6lB&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCcQ6AEwAA#v=onepage&q&f=false

[AZRedhawk44]

i have only seen pictures of ones that bushmaster uses for builds

basically it clamps to the receiver and indexes a straight line down the bore axis

if you re-torqued the barrel nut you could of bent the barrel pin or wallowed the receiver

did you install it to proper torque and then released it 2 times using the proper thread lube?

Yep.  35lbs.  Back off.  35 lbs.  Back off.  35lbs.  I used an anti-seize thread lube.

I don't see how I could have bent the barrel index pin.  Didn't put any pressure on the barrel while torquing the barrel nut or float tube.  Don't think I mucked up the receiver, either.  It shoots well... the FSB is just not aligned with the carry handle.  I would think if I screwed up the receiver then the BCG would have clearance problems while cycling, or wouldn't index against the gas tube properly.  All that seems to work fine.

[AZRedhawk44]

Shot 82%/82%/78% today with the M14 from 600 slow prone.  Rear sight on that is dropping 1-2 MOA per shot due to recoil.  Even tightening up to where it's a pain to turn by hand still has the rear sight lose elevation.  So I don't trust it at all for the rapid stages of the XTC over the next two days.

Tonight I spent an hour in the garage working on the AR and I think it's more or less ready.  Just wish I could find somewhere to put 10 rounds downrange before showing up at the matches tomorrow.  Heck, even a 25m zero confirmation would be nice.  Or even one of those .223 shaped laser-boresighters.

I ended up using a Dillon primer feed tube as an impromptu sight alignment tool.  Wrapped electrical tape around it at two points until it barely fit with friction into the groove of the A2 carry handle.  Clamped gently in place.

After driving pins out of the front sight base, I clamped the barrel in a vise with wood braces, then the FSB in some C-clamps with a long 2x4 as a kind of breaker-bar.  Broke the red lock-tite weld, then aligned with the rear peep while looking down the primer feed tube.  It was pretty far to the right when I started this process and it's pretty well centered now.  Front sight to the far right explains my 25 MOA left impacts, so I think I have it licked.  Drove the pins back in and checked for alignment after all done.  Looks good.

Can't find anywhere to test it out, though.



ETA:  I gerry-rigged a laser boresight from a handheld laser pointer and a shop rag.  Wiggled it around in the back end of the upper receiver until the laser came out the barrel cleanly.  Turns out, that at about 35 feet distance to a wall, the laser has an arc of about 4" it can traverse and still be a well-shaped dot with no refraction/reflection from the rifling.  I centered the dot as well as I could (feeling for the extreme edges of a good dot on the wall and eye-balling a center point), and it is about 1.25 inches square underneath my front sight post.  Since I'm supposed to have convergence at 25 meters for a 300 bsz (@ -1 MOA from 300) and I'm at about half that... I'm happy with the windage now since the front sight hides the dot except for the red splash against the wall from diffusion.    It's pretty well centered.  And elevation was fine even when the thing was off 25 MOA horizontally.  So it seems fine again.

I'm going to run it tomorrow.  I'll take the M14 as a backup, just in case.  But I think it's back on target now.

[RocketMan]

That must be a load off.  Good work, AZ.
Check back and let us know how it shoots with the fix.

[Harold Tuttle]

That's interdasting

Who's make is the barrel assembly?
Were your fsb pins tapered?

[AZRedhawk44]

Shot an 82% XTC.

I'm actually happy with that 82%, considering the obstacles.  Wind was a steady 15+ mph, gusting to 35 and throwing up sandstorms on the Avery 1000 yard range.  Hard enough to push the targets back down in the pits.  I counted at least 5 complete full-value wind reversals during my strings. 

1.  200 standing.  Had no zero to start with.  1st sighter was 9 o'clock wide, 2nd sighter hit the 6 ring at 9 o'clock.  1st few record shots were rough, but I found a rhythm and held the 8 ring or tighter... except for 1 shot where I got gusted hard off target and wound up with a miss by 2 inches, right as I as squeezing the trigger.  1st 10 shots were an earned 76... there were 2 5's that snuck in there from sight issues but the rest were 8's and 9's.  The 2nd 10 shots I got cheated.  I had a good rhythm going after the last half of the 1st 10, and the wind gust on shot 13 took me just outside the 5 ring.  Aside from that, that string was setting up to be a good 86 or higher.  I feel robbed... I was pretty much set to average a mid-80's on standing had my sights been true and the wind hadn't bullied me at the wrong fraction of a second.  Oh well.  Happened to everyone on the line to one degree or other.

2.  200 seated.  Didn't quite trust my zero.  1st string I ended up eating a dirt devil during the timed portion, got an 82 out of it from breaking NPOA and hurrying after the devil.  2nd string I got an 88-1.

3.  300 prone.  I got gusted hard with my 2nd sighter, and it wound up at the 6 ring at 6 o'clock.  That shook my confidence in my zero and I ended up giving another 1 MOA left into the wind.  Wind died down and I got an 87 on 1st string that if it were 1 MOA further over, it would have probably been about a 91-1.  Lots of 9's kissing the 10 ring but not quite there, and some 8's that if they shifted right would have been 9's.  2nd string was an 84.  Lots of wind straight at me during the string, grit in my eyes wrapping around the glasses.

4.  600 prone.  162-2.  12 out of 20 shots in the 8 ring or better.  The wind reversed on me 3 different times, giving the opportunity to adjust for a 1/4 value 20-25mph wind at 600 yards, then a full value the opposite direction, then a half value back the other way.  Each time that happened, I ended up being blown to the land of the 6-ring.  Adjust, get back into the 8 ring or tighter.  I am seeing a difference in my groups after the free-float tube here, though.  Vertical stringing is much lighter now.  I know I had some variance in sight picture to account for the ~3 MOA of vertical wandering across all 20 shots.  Of course, the wind opened my horizontal spread to about 10 MOA for that group.  On a calmer course, I can get somewhere around 175-180 currently.

Stage 4 really felt like I was arm wrestling with a wind giant.  I just gave up trying to mentally wrangle the wind calcs since I didn't know my true zero... Everything I did was based upon the previous stage or the previous shot.  600 slow relied upon a bad zero from 300 prone.  300 prone relied upon a mediocre zero for 200 seated.  200 seated relied upon "lob it 'n guess" efforts from 200 standing.  And 200 standing relied upon a "sorta-good-'nuff" zero in my workshop.

And the flags are looney at Avery.  The 1000 yard range is surrounded by berms on all sides, making the wind swirl and eddy over them.  And somehow, there seems to be a tendency for a southbound wind to blow off the hill it faces.  There are flag poles every 100 yards, and 4 or 5 going across the full 100 point firing range horizontally.  Lots of wind indicators.  Too many.  They often contradict each other, especially near the berms.  And if you're on a firing point that is near the berm... do you listen to the flags in the middle of the range or the "liars" near the berm?  And if so, how close to the berm do you need to be in order to listen to the berm flags rather than the center flags?  I remember often seeing two flags, about 30 yards from each other, flapping in completely opposite direction.

I'd really like to have 10 rounds to shoot in sedate groups of 5 at a 200 yard target, to refine my zero to something meaningful.

Oh, well there's always next year.


Tomorrow is the EIC leg match.  Probably be lots of folks come out for that, that didn't come out the last 2 days.

Total for me was 657-3 out of 800.  82.125%.  Not great.  But I earned it.

Goals for tomorrow:
1. 84% average for standing.
2. 88% average for seated.
3. 90% average for rapid prone.
4. 87% average for slow prone.

Match average goal... 87.25% or 698 out of 800.  So a 700 would please me immensely.

[AZRedhawk44]

Goals for tomorrow:
1. 84% average for standing.
2. 88% average for seated.
3. 90% average for rapid prone.
4. 87% average for slow prone.

Match average goal... 87.25% or 698 out of 800.  So a 700 would please me immensely.

Well, it turns out this was a 50 shot match rather than an 80...

1. 87
2. 89
3. 84
4. 78

Total was a 417-3 out of 500.  84.25 percent. 

Choked on both of the prones.  1st one, I had a mag malfunction... the bolt over-rode my magazine and didn't strip a cartridge, twice.  Dropped mag, whacked it in good and hard, rack bolt... works.  But it cost me 8 seconds or so and I felt hurried all the remaining shots.  Neglected to check the wind and it turns out I needed to come about 2 minutes into the wind.  My first 2 shots in the first mag were awful/hurried over in the land of 7's, and the remaining 8 in the second mag striped the 8 and 9 ring.  1 minute into the wind would have striped the 9/10 ring, and 2 minutes would have put it 9/10/X/10/9.  On the slow prone, I just... failboated.  Couldn't bring my game.  Nibbling at the 7 ring pretty much all the way around the target.  Frustrating.

Need to get a padded glove.  My support hand hurts and has a bruise on it.  Using a cheap work glove right now.  Slinging up tight has me putting a lot of pressure on the pad of my palm just under my support hand index finger.  I didn't sling up very tight for stages 2/3/4 due to that.

[AZRedhawk44]

The wind on yesterday's 600y slow prone was VERY light.  I'm really frustrated that I actually did better in the frantic high wind of Saturday than I did on the calm winds, Sunday.  Heck, I even did better on Friday's prone-only match with my M14, with it's tendency to drop 1-2 MOA per shot.  The M14 has a hooded match aperture though.  And a much longer sight radius.

I've ordered the following toys for my next match in 2 weeks:
1. Padded shooting glove, to sling up tight without it hurting my hand.
2. Turner leather sling... I prefer this type of sling but don't have one long enough for the AR right now and I'm using a GI cotton sling.
3.  1/4 MOA windage adjustment knob for my rear sight with smaller 0.040" aperture.  Hoping the smaller aperture (currently using GI standard flip-sight) helps tighten my 300/600 groups, and finer windage adjustments won't hurt though I'm not good enough right now to take advantage of them, I don't think.  Though with the 7 ring representing about 3MOA of the total real estate in the aiming black and each subsequent ring about 2/3 MOA inwards, it might do me some good if I do actually start nibbling on the 8/9 ring and want to come in to the 10 ring.  I do notice sometimes that the front sight drifts a bit from perfect center in the rear aperture as I'm preparing to send a shot, so a smaller rear means it's that much harder for the front sight to drift from center.  And if it does drift, there's that much less distance for it to go before I notice it is off-center, and I hold the shot until I re-address the sight alignment/picture issue.


Yesterday's EIC score was my first true "Sharpshooter" score in a match, so I am pleased with that.  Didn't have any illusions of winning the EIC match, with the fantastic shooters that were there.  Was hoping for 430 or so.

Frankly, I'm just pleased to have put together a mid/high 80's score for standing.

Still struggling to find a good NPOA for my seated position.  I've given up trying to get close enough to my scope to see my first couple shots between mag changes.  I can't get the scope close enough that it doesn't interfere with the mag change process or slinging up in prep time.  I know I'm capable of a 95 with several X's because I've done it once... recently I seem to be off-center.  I don't think I'm canting the rifle... but I'll watch for it. 

I am getting frustrated at my inconsistency at 500/600 yards, though.  My quasi-mentor has told me to not let the mid range game bother me too much until I have a proper match quality upper with good barrel... but I can't help it. 


I do suspect that my trigger discipline has slumped off, recently... at least for the rapids.  I don't think I'm holding the trigger back and gently resetting for my rapid stages.  Need to re-train that back into me.  Though I know I am doing it on standing and slow prone.

I'll focus on improving the short distance stages into the 90's, and try to have a bit more leniency for the slow prone performance. 

[AZRedhawk44]

Put up an SR-52 target today at the range.  This is the same as the 500y target, just reduced rings for use at 200 yards.

Shot at it with my worst ammo available... some 55gr midway blemish discount bullets, relatively hastily constructed, to try and simulate some of the additional drama involved with true 500 yard shooting.


Earlier this week I ordered a 1/4 minute windage rear sight with 0.040 aperture.  Still have 1MOA elevation adjustments.  Also got a proper shooting glove and a turner 1907 sling.

Result?

185-4x.  Still not true 500y results, but it's by far a personal best.  Prior to that, my best has been a 179-3x shot at 500 yards using Prvi 75gr retail ammo.  My typical SR-52 (500 reduced to 200) performance in the past was around a 170 to 175, and my recent 600 performance at Ben Avery was in the depressing 155-165 range.


That smaller aperture REALLY helps when centering the front sight for finer shots.  Though it might have been the added consistency in sling tension due to the glove deflecting sling-up pinch pain and the thick leather sling.  And I am much more WILLING to make small wind adjustments, rather than full 1 MOA adjustments like before.  Easier to experiment with wind adjustments when each sight adjustment only amounts to a 1/2 inch at 200 yards, rather than 2 inches.  Much less penalty for incorrect guesswork.  It allowed me to get a much more granular windage-zero than I had previously.  I think I'm going to call up White Oak and tell them to change my build from 1/2 x 1/2 sights to 1/4 x 1/4 sights.



I also practiced standing at a 1.5" black circle at 25 yards (6MOA, same as the conventional 200y target) and was able to put about 50% in the black with another 50% in what would be the 8 ring.  So, high 80's or low 90's shooting for standing.


Ready and eager for another match, now.  Really want to stretch this new rear sight's legs at 500 or 600 and see that 185 score manifest at real distance with the 69gr load that seems to work well in my rifle.  And I also want to shoot more standing to cement my typical standing score into the high 80's or possibly break 90 on record.  Need to practice more rapids at some point soon, didn't practice those at all today.  Today was all about that new rear sight and making sure it was sighted in properly, as well as finding a way to work with the new sling and glove.  Love the new setup, though.  Works VERY well.