Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Increase accuracy, eliminate the gas rings


HotRod308

Recommended Posts

  • Replies 65
  • Created
  • Last Reply

Top Posters In This Topic

59 minutes ago, shepp said:

You can get a good look at a T bone steak by sticking your head up abutchers ass but I'd rather take the bulls word for it

 First , what kind of T-Bone are you talking about , looking in the Butchers A$$  & what are you eating :laffs:

 

  Lets get to facts here , The Bullet is almost , if not out of the Barrel before the Bolt unlocks from the Barrel extensions locking lugs , so how does this modification effect accuracy ? Certainly not because of alignment of the Bolt in the Locking Lugs of the Barrel extension , unless you have improper Head Space & even then they would still lock the Breach , never mind what the case may do & that may effect accuracy , but has not one thing to do with the Bolt or its alignment .

 This Rings offer many benefits to a Service Rifle , one , the are a wear item & inexpensively  replaced , two , they too help alignment of the Bolt in the Carrier when Action is fouled , three, they do seal gas signature for proper timing .

 You say your machined to 0,001" clearance , how exactly do you think that that Machined area that has only 0.001" clearance is not contacting the internal bore in the BC for the Bolt ? Does the rest of the Bolt , Cam Pin & front alignment ring ( Front of the Bolt ) also have the same fitment ?

You can see the forward Wear ring in photo below , its shinny from wear .

DSCN2574.JPG 

Link to comment
Share on other sites

11 minutes ago, survivalshop said:

 First , what kind of T-Bone are you talking about , looking in the Butchers A$$  & what are you eating :laffs:

 

  Lets get to facts here , The Bullet is almost , if not out of the Barrel before the Bolt unlocks from the Barrel extensions locking lugs , so how does this modification effect accuracy ? Certainly not because of alignment of the Bolt in the Locking Lugs of the Barrel extension , unless you have improper Head Space & even then they would still lock the Breach , never mind what the case may do & that may effect accuracy , but has not one thing to do with the Bolt or its alignment .

 This Rings offer many benefits to a Service Rifle , one , the are a wear item & inexpensively  replaced , two , they too help alignment of the Bolt in the Carrier when Action is fouled , three, they do seal gas signature for proper timing .

 You say your machined to 0,001" clearance , how exactly do you think that that Machined area that has only 0.001" clearance is not contacting the internal bore in the BC for the Bolt ? Does the rest of the Bolt , Cam Pin & front alignment ring ( Front of the Bolt ) also have the same fitment ?

You can see the forward Wear ring in photo below , its shinny from wear .

DSCN2574.JPG 

 

Link to comment
Share on other sites

51 minutes ago, HotRod308 said:

If you don't like it that's fine. But .001 on one side and .001 on the other side equals .002 total of the clearance.

I missed the part where anyone besides you expressed it in those terms.

Furthermore, @survivalshop is right on the money as usual. While you may well have 0.001" dimensional clearance to the bolt carrier bore, you aren't guaranteed the alignment for clearance, whereas with gas rings that factor is irrelevant.

Link to comment
Share on other sites

Maybe over thinking this but, the reason I did this was after shooting a match I could feel how much harder it was to pull the BCG rearward when it was dirty compared to when it was clean. 

After doing my 308 upper The rifle turned from so what gun that barely brake a 190 at 600yds to shooting a 200 for the first time and shot a 787 that day. 

Reguardless it seams there are some people just don't like new ideas or over think it so much it just can't be that easy.

I have a 223 bolt I did, does one of  the moderators like to try it out?

Edited by HotRod308
Link to comment
Share on other sites

2 minutes ago, HotRod308 said:

Maybe over thinking this but, the reason I did this was after shooting a match I could feel how much harder it was to pull the BCG rearward when it was dirty compared to when it was clean. 

After doing my 308 upper The rifle turned from so what gun that barely brake a 190 at 600yds to shooting a 200 for the first time and shot a 787 that day. 

Reguardless it seams there are some people just don't like new ideas or over think it so much it just can't be that easy.

I have a 223 bolt I did, does one of  the moderators like to try it out?

The idea has actually been discussed here before. Whether or not it has merit depends on what you are out to accomplish. If it's working for you and improves your accuracy, there's nothing to argue against you doing so.

However, broadly generalizing that doing so will make everyone more accurate just isn't the case.

Nobody is trying to discourage you from experimenting, but having every Joe Shadetree try to weld up his bolt and dremel it back down would have dire consequences, not to mention the potential liability. 

Folks here are trying to give you food for thought, or a balanced perspective on something we've discussed before.

Lastly, we really are some abrasive sonsabitches sometimes, it's 'cause we're far too accustomed to one another to be bothered by it. Hang around and you'll see for yourself.

Link to comment
Share on other sites

Well said Matt.,

    It was brought on discussion & I ,as others, have given not only opinions , but some clear facts & I personally am not attacking anyones idea's , but pointing out that , in this case , a more scientific approach has to be provided to show results .

 This may be a helpful idea for Target/Match rifles & as said in your case you believe in it , nothing wrong there . 

Link to comment
Share on other sites

  • 1 year later...

I would be curious to see the velocity numbers used in the test. To properly build statistics about SD and ES it takes more than just a few rounds. And temperature control of the gun and the ammunition would factor in too, maybe humidity and atmospheric pressure too.

Here is a really good article on the subject. I see folks getting axle wrapped about SD calculated from a 5 shot sample a lot. 

https://www.shootingsoftware.com/ftp/Perverse Nature of SD.pdf

Practical Application #1: Evaluating Muzzle Velocities Standard deviation is hard to estimate with precision. When you shoot five shots, and measure something about them, you are taking a sample. From the sample, you hope to make some estimate of what the firearm will do in the long run, over many shots. Since you are dealing with a sample, your estimate of the long term performance will be imperfect, though it may be precise enough to be useful. Suppose that a reloader is unwisely carried away with getting the standard deviation of his handloads down to nothing. He fires five shots, and chronographs each at 2960, 3002, 2982, 2976, and 2981 fps, calculates the standard deviation, 15.04 fps, and feels very pleased that his handloads are so consistent. But are they? It is true enough that his sample of five has a standard deviation of 15.04, but what does that tell us about the long-term performance of his loading technique? If we repeated this same test 100 times, using exactly the same components and methods, then about 95 times out of that 100, we would find a standard deviation between 9.77 and 35.68. Statistically, we say that the true, long term standard deviation could easily be anywhere in that range. So, based on a sample of five, the shooter who thinks he has a superb standard deviation could actually have a standard deviation as high as 35.68, which is about typical for commercial ammunition. It was just his lucky day. The five shots he fired happened to be very close to each other, just by luck of the draw. The reloader that does not recognize this can easily end up chasing phantoms. One day, he shoots test shots, and is very happy with his result. The next, things seem to have “gone to pot”, and he can’t figure out what he is doing wrong. The fact is that nothing has necessarily changed.

Link to comment
Share on other sites

5 hours ago, willbird said:

I would be curious to see the velocity numbers used in the test. To properly build statistics about SD and ES it takes more than just a few rounds. And temperature control of the gun and the ammunition would factor in too, maybe humidity and atmospheric pressure too.

Here is a really good article on the subject. I see folks getting axle wrapped about SD calculated from a 5 shot sample a lot. 

https://www.shootingsoftware.com/ftp/Perverse Nature of SD.pdf

 

 

The fact is one would probably need a minimum of 100 rounds, preferably fired from a machine rest, before the Confidence Interval for the Standard Deviation would be high enough to use as a guide. Possibly more.

Link to comment
Share on other sites

6 hours ago, Sisco said:

The fact is one would probably need a minimum of 100 rounds, preferably fired from a machine rest, before the Confidence Interval for the Standard Deviation would be high enough to use as a guide. Possibly more.

A barrel with a water jacket (engine coolant actually, pumped) might be helpful for the 100 shot string ?

Link to comment
Share on other sites

  • 7 months later...

How on earth did this thread die?  It got better and better.  I actually began to read the SD article with interest.  By the 2nd paragraph it was nap time.  Now I know why I never did finish college.  For the life of me I couldn't pass that graph,  dot,  line stuff.  Yep I'm ignorant with that stuff,  my brain goes to sleep every time.  But throw out some humor and I'm all over it.  Thanks.

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
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...