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Bigger bullet hole theory

In theory 6BR (meaning also improved cartridges) should outshoot .284 at 100-300yards also in F-class. It should, but it didn't in my case. I lost by 1 point with a guy shooting .284 because of bullet hole diameter. As one of our colleagues @TonyinKY
rightly pointed out:
"Do you score by best edge scoring? If so the 30BR will win because of the bigger bullet hole. Other than that I think the 6PPC and 30BR are the same."

Another colleague @Laurie noticed:
"One benefit is as per BR for score - although there is a '30-calibre' scoring rule in F-Class (ie the shot hole edges should be adjusted as if it were made by a .30 bullet when smaller calibres are used), in practice the butts crew will almost invariably score the shot on whether it breaks the line or not - this disadvantages the 6mm even more so 223.".

So, the question is, should I rebarrel from 6BR to .30BR to better cover my mistakes and have a fighting chance against .284 guys?
 
There was a guy complaining at a match about the bullet hole size and the disadvantage of shooting a smaller caliber. Someone popped up and told him shoot closer to the center, problem solved.

We don’t use that rule in the USA. There is nothing right about making bullet holes equal IMO.
 
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In HP shooting in the US (includes F class) there is no 30 caliber rule. Hole has to touch the line to get the point. Laurie shoots in Britain.
 
There was a guy complaining at a match about the bullet hole size and the disadvantage of shooting a smaller caliber. Someone popped up and told him shoot closer to the center, problem solved.

We don’t use that rule in the USA. There is nothing right about making bullet holes equal IMO.
It proves he was right:).
 
It is true a 30 cal has a little more "forgive" if you are scoring edge of bullet hole..... which here in the states, most score shooting disciplines are using (NRA, IBS, and NBRSA both long range and shortrange score; Group in IBS and NBRSA is measured center to center). Which is why the 6PPC (and variants) rules the group game and 30 BR (and variants) rule the score game.
Except these folks
https://ultimatebenchrest.com
They use different targets depending on the caliber the competitor is using. It does even out the playing field a bit.

.284-.243=0.041" is this a wind call issue or rule/scoring issue?

A 6mm usally has a bit less recoil which is a real advantage.... it comes at a cost, you have to make better wind calls.
A 284 win has more forgive in the wind, but you have to deal with the recoil.

CW
 
It is true a 30 cal has a little more "forgive" if you are scoring edge of bullet hole..... which here in the states, most score shooting disciplines are using (NRA, IBS, and NBRSA both long range and shortrange score; Group in IBS and NBRSA is measured center to center). Which is why the 6PPC (and variants) rules the group game and 30 BR (and variants) rule the score game.
Except these folks
https://ultimatebenchrest.com
They use different targets depending on the caliber the competitor is using. It does even out the playing field a bit.

.284-.243=0.041" is this a wind call issue or rule/scoring issue?

A 6mm usally has a bit less recoil which is a real advantage.... it comes at a cost, you have to make better wind calls.
A 284 win has more forgive in the wind, but you have to deal with the recoil.

CW
I like the idea behind ultimatebenchrest. We should import it to Europe.
 
We don’t use that rule in the USA. There is nothing right about making bullet holes equal IMO.

AFAIK, you do as soon as you shoot in a comp with ICFRA regulated rules, ie Target Rifle, Match Rifle, F-Class, Palma etc. As I said, whether the butts crew have a 'bullet gauge', or even know of this issue, is very different thing. They certainly do if you shoot in an international match where the targets are manually scored. How this works out with E-targets - search me!
 
The real question here is whether increasing the diameter of the bullet from 6mm to .30 cal is really worth the effort of having the rifle re-barreled, obtaining new bullets, brass, possibly powder, dies, etc., is actually worth the effort in terms of scoring. In other words, how much are you really going to gain by making the switch?

I have also dropped points when using an F-TR .223 Rem rifle in a 300 yd match. In one case, I called the match director over to check a shot that I thought had touched the line, but the scorer did not. The match director agreed with the scorer and I lost a point. He informed me that the the shot had been out "by the width of a red blood cell". Regardless of by how far, the shot was ruled to be out. Had I been shooting one of my .308s, it's easy to claim the shot would have been in, but there is no way to know how well I would have shot that specific day using a different rifle with noticeably more recoil. It's entirely possible I would have ended up with a lower score having nothing to do with bullet diameter.

My point is that the number of shots you are likely to fire in matches that land right next to the scoring ring where a tiny increase in the size of the bullet hole is potentially going to make a difference is not a large number. Certainly, it may not be zero, but how often would this realistically be expected to happen? Changing calibers would represent a lot of $$$ and effort for a fairly minuscule gain.

IMO - the best reason to change calibers would be to gain the more favorable external ballistics of the .284 Win over the 6mm, not because of the diameter of the bullet. The 6BR is certainly an inherently accurate/precise cartridge, but you're fooling yourself if you don't appreciate how accurately/precisely a .284 Win, or any of several other cartridges, can be loaded by someone willing to make the effort. Any small advantage the 6BR might enjoy in terms of innate precision can easily be overshadowed when the wind comes up. Even at only 300 yd, the difference between predicted wind deflection for a 6mm 105 Hybrid launched at 2900 fps and a .284 180 Hybrid at 2800 fps is about 1" (5.2" versus 4.2", full value 10 mph wind). That is approximately 20 times the difference in bullet diameters. Which do you think will have the greater effect on scores long term?
 
In shooting indoor smallbore on tiny targets I've learned that scoring the holes is a waste of time. Scores with a plug will be substantially different.

Aren't we also entitled to use a plug/gauge in highpower where it may make a difference?
 
The real question here is whether increasing the diameter of the bullet from 6mm to .30 cal is really worth the effort of having the rifle re-barreled, obtaining new bullets, brass, possibly powder, dies, etc., is actually worth the effort in terms of scoring. In other words, how much are you really going to gain by making the switch?

I have also dropped points when using an F-TR .223 Rem rifle in a 300 yd match. In one case, I called the match director over to check a shot that I thought had touched the line, but the scorer did not. The match director agreed with the scorer and I lost a point. He informed me that the the shot had been out "by the width of a red blood cell". Regardless of by how far, the shot was ruled to be out. Had I been shooting one of my .308s, it's easy to claim the shot would have been in, but there is no way to know how well I would have shot that specific day using a different rifle with noticeably more recoil. It's entirely possible I would have ended up with a lower score having nothing to do with bullet diameter.

My point is that the number of shots you are likely to fire in matches that land right next to the scoring ring where a tiny increase in the size of the bullet hole is potentially going to make a difference is not a large number. Certainly, it may not be zero, but how often would this realistically be expected to happen? Changing calibers would represent a lot of $$$ and effort for a fairly minuscule gain.

IMO - the best reason to change calibers would be to gain the more favorable external ballistics of the .284 Win over the 6mm, not because of the diameter of the bullet. The 6BR is certainly an inherently accurate/precise cartridge, but you're fooling yourself if you don't appreciate how accurately/precisely a .284 Win, or any of several other cartridges, can be loaded by someone willing to make the effort. Any small advantage the 6BR might enjoy in terms of innate precision can easily be overshadowed when the wind comes up. Even at only 300 yd, the difference between predicted wind deflection for a 6mm 105 Hybrid launched at 2900 fps and a .284 180 Hybrid at 2800 fps is about 1" (5.2" versus 4.2", full value 10 mph wind). That is approximately 20 times the difference in bullet diameters. Which do you think will have the greater effect on scores long term?
I agree with your line of thinking and I ask myself exactly these questions. I am considering coming back to 6.5 CM at distances beyond 200m. In terms of scoring because: (a) bullet hole diameter, (b) wind. Btw, I don't like the .284 recoil. Recoil produced by 6.5 CM is ok.
 
IFCRA F-Class rules:
"F12.7. When a shot touches the line between two divisions of the target, the competitor will be credited with the higher value. In case of doubt a gauge of 7.82mm diameter (=0.308 inches) will be used (regardless of the actual calibre in use) to determine the value of the shot. The ruling by a Butt Officer will be final."
 
In shooting indoor smallbore on tiny targets I've learned that scoring the holes is a waste of time. Scores with a plug will be substantially different.

Aren't we also entitled to use a plug/gauge in highpower where it may make a difference?
Yes. It's supposed to be at the direction of the pit boss. Individual pit pullers are supposed to consult with the pit boss before inserting a scoring plug into a shot hole.

Of course, with e-targets - it's N/A.
 

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