Blueprinting and accuracy improvement - any proof?

[scout1]

rsilvers, you like to stir the pot way too much ;D

BTW, extreamly happy with your ballistics program.

 

[armorpl8]

I will go on record though as saying that I do not believe a specialized barrel-break-in procedure helps.

Can you see me beating my forehead into the keyboard? I can't believe I am taking this bait.....don't believe it helps what exactly?

 

[rsilvers]

I don't believe it makes for a more precise-shooting barrel.

If you took 200 barrels and just shot 100 of them and then did the 1-shot-clean break in on the other 100 - and then later on (perhaps in mid-life) tested all of them for group size, there would be no measurable difference between set-A and set-B.

 

[NateHaler]

Well, I could pose a challenge. Someone could take a great .308 barrel and stock and put them on a 700 action fresh from Walmart. Shoot 5 groups of 5 rounds each. Then do this two more times with two more Walmart actions. Then send each action to a smith who has an excellent reputation. Then put the barrel and stock on each receiver that has been worked on, and re-shoot the groups. This could be an article for Precision Shooting.

Be a man, and take this on, instead of volunteering somebody else. Get on stage, instead of heckling from the peanut gallery.

 

[rsilvers]

More than looking for someone else to do the test, I was hoping someone could point to such a test having already been done. Perhaps there was an article in Precision Shooting. With so many people doing the service, it would seem like it must have been well tested and an article written somewhere.

I would also like to see the test showing the cryo barrels are more accurate!

Here is a $95 break-in recording for your home stereo. Every industry has the voodoo:

http://www.audioadvisor.com/prodinfo.asp?number=CLBRINREC

 

[Ackman]

Here he goes agains. Silvers just shut up.

 

[holstil]

Professional poo poo slinger?
No profile? 8)
Are you snowed in somewhere?

 

[queen_stick]

I would also like to see the test showing the cryo barrels are more accurate!

There's a guy at my local range with a factory Ruger in 25-06. It shot about 4" groups at 100yards regardless of what he tried. As a last resort, he sent the barrel out and had it cryo'd. He couldn't shoot a group bigger than 1" if he tried since that cryo job. No other work was performed. That's a real-world example, where no other variables were changed, and the process seriously increased accuracy.

With that said, I truly believe this process would only benefit a 'stressed' barrel, whether it's factory or custom. If the barrel shoots to the users liking, then don't bother. As a last resort, to get rid of flyers when shooting groups, this is something to consider. I wouldn't have recommended it before actually seeing a real-world example, with great results.

As a side note...

rsilvers: You've brought up very good questions, and I agree with a lot of your reasoning for the questions. However I think you're taking the wrong approach to get the answers. There's no need to piss everyone off - simply discuss the questions while showing some respect to the people who are more than willing to help out a fellow member.

Walt

 

[clowdis]

I have a Remington Sportsman 78 in .223 that really isn't very impressive in the accuracy department that would make a great candidate for an article about wheter or not there might be an accuracy gain in blueprinting. Trouble is no time until later this summer. Maybe then?

 

[Bob3700]

You can save yourself a lot of time and money by simply finding a set of the old Bob Pease Accuracy booklets. These were published back in the late 80s early 90s.

Bob already did this sort of stuff. Started out with Rem 700 Varmintspecial rifles in .223. Rechambered them for tight neck 222s and in the process squared up the receiver and bbl shoulder. Also pillar bedded the actions into the stocks.

He recorded the accuracy results along the way showing the improvement in group size that each improvement made.

If anyone believes that the accuracy improvements to a Remington or any other factory action are a waist of time, please register to shoot in the matches against me, I need all the help I can get.

Bob

 

[rsilvers]

Thanks.

http://www.amazon.com/Bob-Pease-Accuracy-Collection/dp/B000NMB21G/ref=sr_1_12?ie=UTF8&s=books&qid=1269533106&sr=1-12

 

[rsilvers]

Interesting. In Rifle Accuracy Facts, he says he cannot detect any difference in accuracy with epoxy bedding.

I always just assumed it helped without questioning it, but now I am wondering. By what mechanism is epoxy bedding supposed to improve precision?

 

[NateHaler]

There's a guy at my local range with a factory Ruger in 25-06. It shot about 4" groups at 100yards regardless of what he tried. As a last resort, he sent the barrel out and had it cryo'd. He couldn't shoot a group bigger than 1" if he tried since that cryo job.

Where's the avatar for a BS detector pegging the meter? :

Allow me to cite a similarly credible anecdote: If you eat a packet of Pop Rocks and then drink a Pepsi right away, your stomach will explode. ;D

 

[NateHaler]

Interesting. In Rifle Accuracy Facts, he says he cannot detect any difference in accuracy with epoxy bedding.

Maybe he sniffed too much of that epoxy to notice any difference.

 

[Bob3700]

The epoxy bedding does not improve the accuracy, it ensures that the accuracy that a perfect metal to wood job would create is maintained.

As you well know, wood being a fiberous material will absorb moisture and can change moisture. See reference below:

http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/ch03.pdf

Epoxy materials used for bedding (such as Devcon) have very low coefficients of expansion/shrinkage and NO moisture absorbsion, and excellent Chemical resistance
See reference below.

http://www.freemansupply.com/datasheets/Devcon/devcon-aluminumliquidputty.pdf.

Hopefully, this info will give you a solid basis of informaion for makeing a decision as to whether you want to expoy bed you rifle.


Bob

 

[queen_stick]

That's correct Nate. Nice catch!

 

[armorpl8]

If you eat a packet of Pop Rocks and then drink a Pepsi right away, your stomach will explode.

That isn't funny. When I was in high school and pop rocks were the rage a friend of mine actually knew a guy from another school whose girlfriend had a sister that was found blown to bits in a pile of pop rock wrappers and a half empty Coke...it does happen people.

 

[rsilvers]

What about Epoxy bedding a McMillan fiberglass stock? I always assumed that was needed for good precision but now I am not sure why it would matter.

 

[Spook]

Think about this, when a Remington goes into battery, the surfaces that mate up to allow the trigger to set, hike the rear of the bolt upward (toward the scope base screws) significantly.
What good did all the truing do if the upper lug has less load on it than the lower lug, due to the rear of the bolt being elevated from the concentric and perpendicular axes you create when you true the lug abutments to the receiver bore?
Mr Silvers, Unless you lose the factory bolt and replace it with one that fits the bolt raceway with considerably less tolerance than the factory effort... you're pissing into the wind with regard to large gains in accuracy from most truing efforts.
The truth being that most people dont shoot well enough to be able to tell the difference.
Others mileage will likely vary..but thats the truth as I see it.

 

[rsilvers]

This is what I am trying to get information on.

Let's say you take 30 rifles, and on average, they shoot 1.00 MOA if you do 30 shot groups.

Have a few good gunsmiths true them all but not touch the barrels.

Fire each one 30 more shots and get the overall average.

Would they more likely average 0.95 MOA now, or 0.50 MOA?

For $30,000 we can do a test and find out. I have no idea what the result would be, and I was hoping someone would. But it seems that very few people true an action without replacing the barrel.