Barrel indexing vs muzzle jump

[fgregorio]

This may seem like a silly question at a first glance.
In your opinion, what would be the best barrel index in order to minimize muzzle jump? 6 o'clock or 12 o'clock?
I'm interested only in the inertia (internal ballistic) aspect if it. Not interested in the gas release aspect of it, suppressors, muzzle breaks etc, because those devices are not allowed in palma shooting.
I'm thinking 6 o'clock because since the recoil pivots beneath the bore line, a 6 o'clock index would impart more of a compression force rather thank bending force.
Thoughts?

 

[msinc]

If you are not talking about gas release, brakes, etc., then exactly what part of the barrel is it that you intend to "index"....the rifling????? Maybe a better way to ask would be: what exactly are you indexing the barrel to on a bolt gun in relation to 6 or 12 o'clock???? It has to be me, I have to be missing something here.

 

[Mozella]

Indexing, to control recoil, is important for pistols too, but they're much easier to index. Here's a snapshot from some recent Olympics precision 300 meter pistol trials. The team is from California, in anticipation of California becoming its own country.

The woman on the right, with the pink hearing protection, is competing in the new Transgender Class. The Olympian on the left, without hearing protection, is nicknamed "huh?".

 

[AckleymanII]

Mozella, I took it one step further and have sights on the side of mine.

 

[fgregorio]

Indexing, to control recoil, is important for pistols too, but they're much easier to index. Here's a snapshot from some recent Olympics precision 300 meter pistol trials. The team is from California, in anticipation of California becoming its own country.

View attachment 1024343

Ahahaha that's absolute gold!!!! Even on the standards of planet Melmac that would stick

 

[fgregorio]

If you are not talking about gas release, brakes, etc., then exactly what part of the barrel is it that you intend to "index"....the rifling????? Maybe a better way to ask would be: what exactly are you indexing the barrel to on a bolt gun in relation to 6 or 12 o'clock???? It has to be me, I have to be missing something here.

So just think barrel harmonics. Internal ballistics. Barrels are not straight. If the muzzle of the banana barrel is pointing down will the rifle recoil straighter back or not? Think that it is a f class rig or a benchrest rig?

 

[T-shooter]

Indexing, to control recoil, is important for pistols too, but they're much easier to index. Here's a snapshot from some recent Olympics precision 300 meter pistol trials. The team is from California, in anticipation of California becoming its own country.

The woman on the right, with the pink hearing protection, is competing in the new Transgender Class. The Olympian on the left, without hearing protection, is nicknamed "huh?".

View attachment 1024343

 

[Texan]

So just think barrel harmonics. Internal ballistics. Barrels are not straight. If the muzzle of the banana barrel is pointing down will the rifle recoil straighter back or not? Think that it is a f class rig or a benchrest rig?

Huh?

It's way more gooder when the banana barrel is pointing straight.

 

[bsekf]

fgregorio, you are chasing your tail. Subject has been discussed, but there are so many variables. I gave up and just do ladders trying to get exit at the same place in the harmonics. IMHO the index will change as the throat wears, or you change bullet and/or powder lots.

But testing is fun!

Bill

 

[butchlambert]

So just think barrel harmonics. Internal ballistics. Barrels are not straight. If the muzzle of the banana barrel is pointing down will the rifle recoil straighter back or not? Think that it is a f class rig or a benchrest rig?

If you have been around more than a day or 3, you will know that it is virtually impossible to drill a banana path through a barrel blank.
You need to quit wasting time on this and spend your time at the range.

 

[Mikemci]

It's morons like those two, that make the rest of us, have to fight constantly to retain our right to gun ownership.

 

[fgregorio]

Guys, I can't hide my disappointment with the replies that I've been getting in this forum.
A bit of background: I train and dry fire 2.5 hours a day. I shoot at the range 2-3 days a week totalling 15 hours of training and live fire on top of the 12.5 hours of dry firing and training. So 27.5 hours of training in total EVERY WEEK of the year. Add reloading, ancillary activities and travel time and you've deduced by now that shooting is my profession, my life. I am gearing for the world long range championships in new Zealand and I want to win it. My financial situation easily allows me to do this lifestyle.
Although I can shoot palma producing the same groups that many other shooters produce using a rest and scope, I am trying to eke out of my rifle/ ammo any fraction of moa that I can extract.
I am left handed and am getting another 2 bartleins, this time in a left twist.
Last post I asked about recoil torque and left twist and the answers were useless.
This time I asked, since barrels are not perfectly straight, whether if the curve should point to 6 o'clock or to 12 o'clock in order to maximize the efficiency of the harmonics of the barrel. Simple question that attracted 10 useless replies.
For the ones that possess the knowledge, can I please have a productive answer to my questions?

 

[Outrider27]

...I am left handed and am getting another 2 bartleins, this time in a left twist.
Last post I asked about recoil torque and left twist and the answers were useless.
This time I asked, since barrels are not perfectly straight, whether if the curve should point to 6 o'clock or to 12 o'clock in order to maximize the efficiency of the harmonics of the barrel. Simple question that attracted 10 useless replies.
For the ones that possess the knowledge, can I please have a productive answer to my questions?

A small correction. You asked about indexing the barrel, but until your above post, you did not specify what you wished to index it in relation to. Had you specified that you wised to index it with regard to bore curve up or down in your original post, you might have gotten some useful answers.

That having been said, unfortunately, we have no insights to offer when trying to use bore curve as an indexing factor. We have just run ladder tests and worked from there, sometimes using pressure pads in various locations in the barrel channel to change harmonics to see if we could improve accuracy, but mostly just tuning the load to see if we could make an improvement, but not with hopes of competing at your level.

 

[jcampbellsmith]

fgregorio
You asked a good question. In the absence of replies, I suggest that you get two rifles set up identically - apart from the indexing. Once you have suitable loads for your rifles, you will need to do a blind trial. However it might be better to focus on

• Wind reading
• A stock that is as recoil insensitive as you can make it

Good luck.
JCS

 

[alinwa]

This may seem like a silly question at a first glance.
In your opinion, what would be the best barrel index in order to minimize muzzle jump? 6 o'clock or 12 o'clock?
I'm interested only in the inertia (internal ballistic) aspect if it. Not interested in the gas release aspect of it, suppressors, muzzle breaks etc, because those devices are not allowed in palma shooting.
I'm thinking 6 o'clock because since the recoil pivots beneath the bore line, a 6 o'clock index would impart more of a compression force rather thank bending force.
Thoughts?

I index and I test this, a lot. This is mainly all I'm doing right now re shooting....I'm not going to go into any detail on this forum because the flies will swarm all over it but do yourself a favor and try just past 6:00, maybe even 6:30-ish, I sometimes go up to near 7:00 on big 338's with barrels over 30"

 

[hpshooter]

" I am gearing for the world long range championships in new Zealand and I want to win it."

Wish I had the knowledge base to help. I have wondered about the very question you asked myself.

Hopefully your dedication and practice will pay off at the world shoot and your skill will prevail.

Sincerely,
T W Hudson

 

[338 Mollett]

I just chambered a barrel that was over 80 thou.out at at the muzzle so I timed the high end up, the bore also has a reverse taper. To be fair to the barrel folks I will keep the their name mum for now but we will see if it shoots.

 

[seymour fish]

It's morons like those two, that make the rest of us, have to fight constantly to retain our right to gun ownership.

You shoot like dat in Chicago, get a free obammy 9

 

[Park ranger]

That was my excuse for not winning the WLRC at Camp Perry in 2015, my barrel was indexed wrong.

 

[ireload2]

Ask Herr Guffey.