Jump to content

Something followed me home today...


Unobtanium

Recommended Posts

  • Replies 69
  • Created
  • Last Reply

Top Posters In This Topic

By the very fact that something is hanging off of the M4 barrel (Magazine Tube, Forward Stock) and it is not free floating throws all these theories out the window! Every time you bench rest or hold the M4 while shooting you are potentially changing the MOA. The M4 is one BadAss shotgun, accurate as He11 but it is not a precision rifle PERIOD!

 

Not really, thermal expansion against the mag cap at the very end pits a lot more tension against the barrel than a normal bracing with hands or sandbag.

Link to comment
Share on other sites

Imthnk tjat was was a bit of a joke.

I know, but some of the logic trains here needed clarity I feared. We have people saying that holding the forend is equal to thermal expansion impingement. We have people saying it's the ammo who releasing the barrel fixes the issue instantly. We have people saying 12moa doesn't matter. So I figured...

Link to comment
Share on other sites

This picture details what I am talking about. I understand some shooters cannot stack slugs and flinch so badly that it's a moot point, but for some of us, this is meaningful. As SD said, when using irons, I did not notice the issue, when using the RDS that was not touching the barrel, the shift was meaningful. Notations written on target. Shot #1 was the top right, using the RDS. Shot #2 was top left, using irons through the RDS. I then fired 25 rounds of bird-shot as fast as possible. Shot #3 was then made using the RDS bottom right. Shot #4 was then immediately made using irons bottom left, followed by a confirmation shot (#5), bottom right using the RDS. It is stacked with shot #3.

 

20171019_144121 (1).jpg

Link to comment
Share on other sites

This picture details what I am talking about. I understand some shooters cannot stack slugs and flinch so badly that it's a moot point, but for some of us, this is meaningful. As SD said, when using irons, I did not notice the issue, when using the RDS that was not touching the barrel, the shift was meaningful. Notations written on target. Shot #1 was the top right, using the RDS. Shot #2 was top left, using irons through the RDS. I then fired 25 rounds of bird-shot as fast as possible. Shot #3 was then made using the RDS bottom right. Shot #4 was then immediately made using irons bottom left, followed by a confirmation shot (#5), bottom right using the RDS. It is stacked with shot #3.

 

[ATTACH=CONFIG]3501[/ATTACH]

 

That pretty much defines the issue. Thanx! Would be awesome to see if anyone else has this issue as well.

 

Very interesting. Who would have thought

Link to comment
Share on other sites

Need to mount your RDS out at the end of the barrel.

 

Or, we need to develop a new thermal expansion compensating mag tube cap...

 

But seriously, need to do this with more barrels. Possibly more M4s. Side by side testing. One thing that seems odd that a barrel deflection resulting in a 12 MOA of difference would allow for the sights to follow in line that perfectly... I know the front sight is at the tip of the barrel but still...

Edited by AVATactical.com
Link to comment
Share on other sites

Need to mount your RDS out at the end of the barrel.

 

Or, we need to develop a new thermal expansion compensating mag tube cap...

 

But seriously, need to do this with more barrels. Possibly more M4s. Side by side testing. One thing that seems odd that a barrel deflection resulting in a 12 MOA of difference would allow for the sights to follow in line that perfectly... I know the front sight is at the tip of the barrel but still...

 

Well, then other people who question it should get to testing, is my opinion. I am not selling a product, nor am I pushing an agenda. It is not on me to "prove" anything, to anyone, as so many people on this forum seem to make it out to be. I am simply sharing what I have discovered to be true of MY situation, and any "proof" offered, has been gratis.

 

Were I trying to cause people to change their practices, buy my products, or adopt my methods, I would feel more responsibility for cause/effect establishment. Since I am doing none of the above, I'd encourage people who have questions to do their own testing.

 

This post is not directed at you, nor is it a tongue-in-cheek dig at your status as a manufacturer (your products have nothing to do with this phenomenon in my observation, anyways), but mainly at those who have directed derision at my observations and/or demanded more "proof", or whatnot, as though I were a salesman pushing something at them.

 

To me, the POI tracking with POA of the irons makes sense. They are both at the same locations on the barrel (the rear sight is near enough the barrel that it "counts" for

 

That said, this is part of why I went SBS. Less barrel length to expand/contract. More rigid barrel (less length to be bent). Etc. That, and all the other awesome reasons to go SBS, lol.

 

It also makes sense that JUST NOW we are seeing this phenomenon, with receiver mounted RDS becoming more popular with MI, and Scalarworks making very viable methods.

 

Also, I asked long ago, a question, and it got a few answers that seemed odd...now, not so much...

 

https://forums.benelliusa.com/showthread.php/33601-Benelli-super-90-series-and-m4-slugs-and-cleaning-and-zero-shift?highlight=cleaning

 

This guy uses an Aimpoint, and..."has to chase his zero sometimes". Could it be that his established zero was established with a hot barrel, after chasing said zero, and then when he gets back to the range, cold, it is no-longer zeroed? A 12moa or greater shift could indeed cause him to miss the entire target at 100 yards....especially a 11x22" target, when aiming dead-center...hmmmm...things clicking into place...

Edited by Unobtanium
Link to comment
Share on other sites

For the record, when I asked if you still had your rig, i was going to see if you wanted to test with more barrels I have in hand. When I get out I will test mine. Hoping others do as well - wasn't intended to be directing you to do more testing.

 

Since you said that once it was hot, if you released the mag tube cap and re-secured it you were all back on target. Did you let it cool down and see if the cap was tight enough for work at resting temp? Was it on target with the cap like this when cool? If so, just adjusting torque spec downwards would seem to be the solution, it's detented after-all.

Link to comment
Share on other sites

For the record, when I asked if you still had your rig, i was going to see if you wanted to test with more barrels I have in hand. When I get out I will test mine. Hoping others do as well - wasn't intended to be directing you to do more testing.

 

Since you said that once it was hot, if you released the mag tube cap and re-secured it you were all back on target. Did you let it cool down and see if the cap was tight enough for work at resting temp? Was it on target with the cap like this when cool? If so, just adjusting torque spec downwards would seem to be the solution, it's detented after-all.

 

I found that the hotter the barrel, the tighter the cap if tightened when cool. When I loosened and then re-tightened it with the barrel hot, and it cooled, I could then tighten it a bit more using the same pressure.

 

I feel you are correct on "torque to spec". That is what I was doing, effectively. "Spec" being "as tight as I can turn it un-aided with one hand". It RTZ'd perfectly, then.

 

I may well try adjusting torque downward.

Edited by Unobtanium
Link to comment
Share on other sites

It's possible that tightening as tight as you can isn't required and has a bad result.

I re-read and understand. I will try this test out. My grip strength isn't special, but it is above average. I believe you are well aware of my penchant for torque. I bought multiple torque wrenches and now demand a torque spec of every manufacturer I deal with, lol! I suppose I need to extend this to the mag cap...

Link to comment
Share on other sites

Putting this nonsense to rest!

Benelli M4 18.5" Barrel, Full length Benelli Magazine, Aimpoint Micro T-2, Etekcity Lasergrip 774, 50 feet, 20" x 24" Target.

14 shots, Temperature measurement points Barrel rear hanger, front hanger - Magazine same temperature within 1 degree anywhere on magazine. I'm sure I could tighten things up with a 14" barrel, shorter is better, HaHaHa

 

IMG_6940.jpg

IMG_6941.jpg

M4-1.jpg

IMG_6942.jpg

I can hear the haters now, I lucked out on my FCG, now I lucked out on my magazine, I just plain lucked out on my M4!

 

Now go out and shoot!

 

I think my Benelli Telescoping Stock is having an effect on my groupings being pinned at it's full extension, anyone having this problem, HaHaHa

Edited by Intervention
Link to comment
Share on other sites

What's to hate? Nice shooting! Must be the cheese grater on the end of the barrel.;) Whatever is going on with U's shotgun, I don't know but, I don't think it's inherent to all M4's. Iv'e not done any testing for data etc., etc., but mine does not throw flyers like U is experiencing and everything that I have read about them accuracy-wise has been glowing with the exception of his.

 

Also, it seems he no longer has the gun as he stated he is currently M4-less, waiting for his SB M4?

Link to comment
Share on other sites

Must be the cheese grater on the end of the barrel.;)

 

The cheese grater along with my standard no pistol grip stock gets me into the trap range that requires a minimum barrel size of 20". Drives some of them nuts there, probably ban black shotguns next!

 

it seems he no longer has the gun as he stated he is currently M4-less, waiting for his SB M4?

 

Must be an imaginary problem then, I can't wait to hear the problems he has with the 14" :)

Edited by Intervention
Link to comment
Share on other sites

The cheese grater along with my standard no pistol grip stock gets me into the trap range that requires a minimum barrel size of 20". Drives some of them nuts there, probably ban black shotguns next!

 

 

 

Must be an imaginary problem then, I can't wait to hear the problems he has with the 14" :)

 

Imaginary...something reproducible, documented with photos and video...

 

Good shooting, I guess I need to now say that I am glad you do not work on any of the aircraft I have flown on. "But this 747 over here didn't have the problem the pilot is reporting on that one, so it's BS, I even tested this plane over here for it..."

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...