• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Bloop Tubes & Accuracy

257Roberts

My 6.5 Creedmoor XTC has a 26" barrel. Its an honest 1/4MOA gun right now if I do my part [haha, bench & scope], I have been using it as is for iron sights as well.

I've been considering a bloop tube, just so the sight click correlation matches my other rifles with 30" barrels.
Thus far, my eyes have been very good, but theres no denying that eyes degrade over time as well, so far no glass or correction.

My question, what have folks seen happen to accuracy when adding a "bloop"? No change? Big change? Enough to redo your load recipe to find a new accuracy node?
 
I am by no means an expert, here is my take however. The "bloop" part of the equation is only of minor consequence. The big change, if there is one, will be due to barrel harmonics when you add weight and length to the muzzle end. So to give you my opinion on your need to redo your load recipe is, a definite maybe.

Extending the sight radius to a known quantity will however show definite benefit when it comes to confidence in making holdovers and the like.
 
Aside from the sight radius that some tubes allow you to change, I personally view bloops as a huge swing at tune. For goodness sakes...you just added a weight to the bbl that extends several inches. Of course it will change tune. So yes, they can both help or hurt accuracy..more specifically, tune. I think all this stuff posted about one shielding the bullet from the wind is horse hockey.

There...That should wake up the peanut gallery.;)
 
You probably will need a new load but not necessarily, the magnetospeed chronos don't seem to change the groups a great deal but alter the point of impact.
Turn the sight upside down and hang it off the bottom for shooting with a scope.
 
The velocities should remain unchanged but the barrel harmonics may change. They may change for the better as much as it could change for the worst. With irons, you will not be shooting 1/4 inch groups as you were the scope. Most of the change will be from optics to irons.
 
Since you're shooting 6.5 creedmoor and not a "Palma" caliber... I guess I don't see the point of shooting irons since you're pretty much in the match rifle/any rifle class due to the caliber anyway.
 
tflorman said:
Since you're shooting 6.5 creedmoor and not a "Palma" caliber... I guess I don't see the point of shooting irons since you're pretty much in the match rifle/any rifle class due to the caliber anyway.
Click to expand...
Some prone matches still require you to shoot irons for a portion of the match.
 
I think some of the idea behind a bloop tube was that it allowed the muzzle to point straight ahead when the barrel was at its extreme end of the harmonic. I dont know why that would be a benefit, but if damping the amplitude is a goal, any weight at the muzzle will do it. Anything is worth a try.
 
karrarararararar said:
Some prone matches still require you to shoot irons for a portion of the match.
Click to expand...
Perhaps you're right, I guess it depends on where you shoot, but I've never seen a match with that in the program in Colorado... not that that means much. In the end, do what makes things more fun for you.
 
tflorman said:
Perhaps you're right, I guess it depends on where you shoot, but I've never seen a match with that in the program in Colorado... not that that means much. In the end, do what makes things more fun for you.
Click to expand...
Our regional and state matches in North Dakota require it. I believe there are some matches in Minnesota and Wisconsin that require it too.
 
A bloop tube would likely cause some minor changes in harmonics.
For XTC or shooting prone with irons, it’s not enough to bother worrying about. There’s less than 10 shooters in the world with holds that good that it could matter.
 
Dave Marshall said:
A bloop tube would likely cause some minor changes in harmonics.
For XTC or shooting prone with irons, it’s not enough to bother worrying about. There’s less than 10 shooters in the world with holds that good that it could matter.
Click to expand...

I agree with Dave here in this respect...I too believe it is not enough to worry about. Back when I first began using a 6.5x47 match prone build, it was metallic sights. I use a RightSight front sight to include the barrel mount for the sight. However, during load development, I was utilizing a mounted scope. Once the load was tuned, I installed the front sight mount, loaded up the metallic sights and it was off to the races. !0's and X's (as long as I did my part) but later I discovered, during an Fclass match where I remounted a scope and shot FT/R, accuracy was not the same as load development. When I removed the front sight mount, Voila! Noted; the barrel is a medium contour Palma. Just the front sight mount was enough to shift POI and open the group slightly but apparently not enough to create conflict when using metallics. It basically went from .350'' group (scoped load development) to almost .856" with sight mount installed. I would imagine a mounted tube would have similar result. But again, perhaps not enough to be concerning.
 
It might change something, but does it really matter? If you are shooting irons, the front sight and base themselves will naturally have some kind effect on the barrel harmonics, but you need them there either way. If you want/need to use a bloop tube, just think of the tube as part of the front sight assembly. It has to be there, so just deal with whatever the result of the assembly being attached happens to be. I’ve used tubes to correct sight radius on my last several palma barrels, and I’ve never noticed any issues with accuracy.

To answer the other guy’s question of why to shoot irons at all; in the upper Midwest (and most other parts of the country), all mid and long range prone matches require irons be shot for at least a part of the match. I hope that never changes, because it’s an important part of the game.
 
Last edited:
Pawnee Bill said:
What the hell is a bloop tube? The only other "bloop tube" I know of was the M-79 Grenade Launcher. I guess I need to get out more often.
Click to expand...
Its basically a piece of pipe clamped onto the muzzle end of the barrel to extend sight radius. Most aperture sights are calibrated at a specific sighting radius length, and also extending the front sight towards the target helps the eye focus better as well. Bloob tubes don't do anything to the flight characteristics of the bullet, but like others have said can possibly change barrel harmonics some.

In my case, I have a 26" XTC gun that I could certainly run as is, but extending the front sight out another 4 inches would make adjustments/aperture sizes consistent with my other rifles.
 
coldboreshot said:
Look up Norman Houle, he makes them or take a look on almost any high end smallbore match rifle. It's a barrel extension that extends sight picture for more accurate sight dope.
Click to expand...

My bad , wrong recipient. I meant to respond to Pawnee Bill so Pawnee if your reading, this is the explanation.
 
You must log in or register to reply here.

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Classified Ads

Forum statistics

Threads
166,234
Messages
2,213,724
Members
79,448
Latest member
tornado-technologies

Share This Page

Back
Top