Comb height questions

[SqHunter]

I am working on modifying a wooded Pharr pattern stock. This is just for fun, btw. I have no plans to compete with it or try to cause trouble. I am just interested in stock design.

The idea was to thin and add cast to the buttstock as it puts my head too far to the left in its original form. I would like to bring the comb up just a touch as well to match my Wooster stock. Do you put some kind of rod in the bore to measure comb height? Is there a standard?

Also, as I understand the rules the center of the comb can come only to the center of the bore, but a roll is allowed also? I am assuming this is to cover Anschutz Sporter stocks, but it is a little ambiguous. I swear I have seen standard class stocks that appeared higher than that. Does roll angle matter as far as rules go, and is there a standard on how far it comes back? What is the consensus?

Last, where is the stock box that is used to determine legality? I would like to take this one there and have it evaluated when I am done. If it works, that is.

Here are the rules as I know them:

]]] The comb shall not extend above the centerline of the bore, but Monte Carlo roll may rise 1/2 inch on the off side.

[ter]

I know they had the stock box at Ridgway. Back in the day, I was told there were only 2 jigs in existence. Maybe the other is in Mexico?
I do remember files, rasps, hacksaws were available at Ridgway for that custom fit. Great to watch someone hack down a 1907 barrel to make weight. Good memories.

[acorneau]

I am working on modifying a wooded Pharr pattern stock. This is just for fun, btw. I have no plans to compete with it or try to cause trouble. I am just interested in stock design.

Well, that right there means do whatever you want and don't worry about any rules (which you ask about the rest of the post). Be that as it may, I'll answer as best as I can as if you were wanting to make your stock fit the rules.

The idea was to thin and add cast to the buttstock as it puts my head too far to the left in its original form. I would like to bring the comb up just a touch as well to match my Wooster stock. Do you put some kind of rod in the bore to measure comb height? Is there a standard?

If you can look down the bore (the way you're not supposed to look down a gun) and see the comb then you're on the bleeding edge. If the comb blocks the view beyond then you're too high.

Also, as I understand the rules the center of the comb can come only to the center of the bore, but a roll is allowed also? I am assuming this is to cover Anschutz Sporter stocks, but it is a little ambiguous. I swear I have seen standard class stocks that appeared higher than that. Does roll angle matter as far as rules go, and is there a standard on how far it comes back? What is the consensus?

Like a lot of other things, the rules are not clearly defined in this respect. It's up to the match director's discretion on how to interpret the rule.

Last, where is the stock box that is used to determine legality? I would like to take this one there and have it evaluated when I am done. If it works, that is.

The infamous "jig" exists in two places; one at Ridgway Rifle Club and one at the Whittington Center. The one at Ridgway is in the clubhouse and available whenever I've been there for Nationals. Where the one at the Whittington Center is, and who actually knows how to work the thing, is a complete mystery.

The "jig" at Ridgway is clear plexiglass (?) so it's little hard to see.

IMG_2532.jpeg

Hope that helps.

[SqHunter]

I am working on modifying a wooded Pharr pattern stock. This is just for fun, btw. I have no plans to compete with it or try to cause trouble. I am just interested in stock design.

Well, that right there means do whatever you want and don't worry about any rules (which you ask about the rest of the post). Be that as it may, I'll answer as best as I can as if you were wanting to make your stock fit the rules.

The idea was to thin and add cast to the buttstock as it puts my head too far to the left in its original form. I would like to bring the comb up just a touch as well to match my Wooster stock. Do you put some kind of rod in the bore to measure comb height? Is there a standard?

If you can look down the bore (the way you're not supposed to look down a gun) and see the comb then you're on the bleeding edge. If the comb blocks the view beyond then you're too high.

Also, as I understand the rules the center of the comb can come only to the center of the bore, but a roll is allowed also? I am assuming this is to cover Anschutz Sporter stocks, but it is a little ambiguous. I swear I have seen standard class stocks that appeared higher than that. Does roll angle matter as far as rules go, and is there a standard on how far it comes back? What is the consensus?

Like a lot of other things, the rules are not clearly defined in this respect. It's up to the match director's discretion on how to interpret the rule.

Last, where is the stock box that is used to determine legality? I would like to take this one there and have it evaluated when I am done. If it works, that is.

The infamous "jig" exists in two places; one at Ridgway Rifle Club and one at the Whittington Center. The one at Ridgway is in the clubhouse and available whenever I've been there for Nationals. Where the one at the Whittington Center is, and who actually knows how to work the thing, is a complete mystery.

The "jig" at Ridgway is clear plexiglass (?) so it's little hard to see.

IMG_2532.jpeg


Hope that helps.

Thank you, that does help. I wish I had known that the jig was at Whittington. I have been there. I hope to make the Nationals at Ridgeway someday, so I will try to take it there eventually.

Thanks for the explanation of the comb and roll over. I had thought it was something like that. It is hard to measure though. Cleaning rods bend and they have handles, so getting an absolute straight line through the bore is difficult.

Do you know how to measure the forearm also? It is measured from center of bore in the rule book. How do you do that from the side or lateral view?

[SqHunter]

I know they had the stock box at Ridgway. Back in the day, I was told there were only 2 jigs in existence. Maybe the other is in Mexico?
I do remember files, rasps, hacksaws were available at Ridgway for that custom fit. Great to watch someone hack down a 1907 barrel to make weight. Good memories.

I plan to take the rasp and lots of sandpaper where ever I go

I am not sure about the barrel though. I tried to draw file a bull barrel to make taper once. Just once...

[375Short]

Allen gives great answers and usually has pictures which are a big plus. I take a different approach and ramble on with poor sentence structure and misspelled words which vexed both my English and Spanish teachers.

If you don’t want to compete with the finished product it could look like a twisted violin. If I hit on something that felt like offhand comfort and perfection I then would like for it to be useful as a match legal stock . That brings us to interpretation of the rule book. It covers some measurements fairly clearly. Like trigger guard dimensions, stock depth and width. Comb height seems clear enough. With scope height and mounting position defined that helps a good deal determining practical comb configurations. The whole book needs to be edited. Over time it’s just a bunch of added in stuff without a lot of thought cleaning up the old stuff and the author assuming historical knowledge fills in the blanks. That doesn’t work.

The Jig - we discussed the jig several years ago on this forum. In summery, a jig does not exist in the current rule book (have not read the 2024/25 version) A jig is not needed to check the rifle standards as they appear in the current rule book. No rule, dimensions our guidance on the proper construction and calibration of the jig. Other than conversations about the past and an object to gawk at in the Silhouette museum it’s currently not relevant. I will say it’s a cool looking and well made gadget. Kind of has a medieval torture device look to it and may have caused about as much pain. That said, it was a significant part of our past and is interesting. Apparently, as pain will do, it seared in many strong memories, emotions and opinions.

Someone wrote on another post Silhouette is simple. It is, then we pile on lots to make it not. More written words in a book don’t always add clarity. Well written, clear, simple as possible to meet our needs would be great. Someone with no experience in the game should be able to read the instructions and play the game. I think currently one may read the instructions, decide it’s very ambiguous, complicated, offering more questions than answers and thus become bewildered and seek other forms of entertainment. Not everyone can be as stubborn, tenacious, and passionate about this great sport as we are.

[Grantmac]

Allen gives great answers and usually has pictures which are a big plus. I take a different approach and ramble on with poor sentence structure and misspelled words which vexed both my English and Spanish teachers.

If you don’t want to compete with the finished product it could look like a twisted violin. If I hit on something that felt like offhand comfort and perfection I then would like for it to be useful as a match legal stock . That brings us to interpretation of the rule book. It covers some measurements fairly clearly. Like trigger guard dimensions, stock depth and width. Comb height seems clear enough. With scope height and mounting position defined that helps a good deal determining practical comb configurations. The whole book needs to be edited. Over time it’s just a bunch of added in stuff without a lot of thought cleaning up the old stuff and the author assuming historical knowledge fills in the blanks. That doesn’t work.

The Jig - we discussed the jig several years ago on this forum. In summery, a jig does not exist in the current rule book (have not read the 2024/25 version) A jig is not needed to check the rifle standards as they appear in the current rule book. No rule, dimensions our guidance on the proper construction and calibration of the jig. Other than conversations about the past and an object to gawk at in the Silhouette museum it’s currently not relevant. I will say it’s a cool looking and well made gadget. Kind of has a medieval torture device look to it and may have caused about as much pain. That said, it was a significant part of our past and is interesting. Apparently, as pain will do, it seared in many strong memories, emotions and opinions.

Someone wrote on another post Silhouette is simple. It is, then we pile on lots to make it not. More written words in a book don’t always add clarity. Well written, clear, simple as possible to meet our needs would be great. Someone with no experience in the game should be able to read the instructions and play the game. I think currently one may read the instructions, decide it’s very ambiguous, complicated, offering more questions than answers and thus become bewildered and seek other forms of entertainment. Not everyone can be as stubborn, tenacious, and passionate about this great sport as we are.

I agree completely and there are simple ways to do it.
Regulate the height of the scope to be from the center of the bore at the chamber end and the comb doesn't need regulation: it will go where it's comfortable and can even be adjustable if it makes weight. WHICH WILL MAKE RIFLES FIT EVERYONE IN SIMILAR WAYS.
Regulate the depth of the forearm from the bore as well although center of barrel is easy enough.

That's literally it for stock shape. They already don't look like any hunting rifle so why bother pretending

[SqHunter]

Allen gives great answers and usually has pictures which are a big plus. I take a different approach and ramble on with poor sentence structure and misspelled words which vexed both my English and Spanish teachers.

If you don’t want to compete with the finished product it could look like a twisted violin. If I hit on something that felt like offhand comfort and perfection I then would like for it to be useful as a match legal stock . That brings us to interpretation of the rule book. It covers some measurements fairly clearly. Like trigger guard dimensions, stock depth and width. Comb height seems clear enough. With scope height and mounting position defined that helps a good deal determining practical comb configurations. The whole book needs to be edited. Over time it’s just a bunch of added in stuff without a lot of thought cleaning up the old stuff and the author assuming historical knowledge fills in the blanks. That doesn’t work.

The Jig - we discussed the jig several years ago on this forum. In summery, a jig does not exist in the current rule book (have not read the 2024/25 version) A jig is not needed to check the rifle standards as they appear in the current rule book. No rule, dimensions our guidance on the proper construction and calibration of the jig. Other than conversations about the past and an object to gawk at in the Silhouette museum it’s currently not relevant. I will say it’s a cool looking and well made gadget. Kind of has a medieval torture device look to it and may have caused about as much pain. That said, it was a significant part of our past and is interesting. Apparently, as pain will do, it seared in many strong memories, emotions and opinions.

Someone wrote on another post Silhouette is simple. It is, then we pile on lots to make it not. More written words in a book don’t always add clarity. Well written, clear, simple as possible to meet our needs would be great. Someone with no experience in the game should be able to read the instructions and play the game. I think currently one may read the instructions, decide it’s very ambiguous, complicated, offering more questions than answers and thus become bewildered and seek other forms of entertainment. Not everyone can be as stubborn, tenacious, and passionate about this great sport as we are.

I agree completely and there are simple ways to do it.
Regulate the height of the scope to be from the center of the bore at the chamber end and the comb doesn't need regulation: it will go where it's comfortable and can even be adjustable if it makes weight. WHICH WILL MAKE RIFLES FIT EVERYONE IN SIMILAR WAYS.
Regulate the depth of the forearm from the bore as well although center of barrel is easy enough.

That's literally it for stock shape. They already don't look like any hunting rifle so why bother pretending

I hunt squirrels with a modified McMillan silhouette stock, and have hunted deer with a 40x clone in a Pharr stock. That is actually what brought me to silhouette, to try and figure out what made a good offhand hunting rifle. I still hunt, no deer stands. All shots offhand or leaning on a tree.

What I wish I could do is take the relationship of bore to comb and scope and make it such that the scope sat as low as possible. That would flatten the relative trajectory which is important in squirrel hunting. The end result would look like a schuetzen rifle, only with scope instead of iron sights. For this reason I wish our sport allowed shuezten rifles to compete. It would allow innovation. They don't fit in the rules now because the drop at toe would be too low too fit in the jig.

From that perspective, what part of stock design helps in offhand shooting? Position of the offhand and elbow, relation of head and neck, and perfect trigger finger placement? What else?

It has occurred to me that all of this would be easier to sort out if we allowed the MDT chassis stock to compete.

[Grantmac]

Greater drop at heel and forearm depth would do what you want.
Both could be very easily achieved with almost any factory stock if adjustable butt plates and palm rests but I digress.

Apparently the jig doesn't matter anymore, is there still a maximum drop at heel?

[acorneau]

Apparently the jig doesn't matter anymore, is there still a maximum drop at heel?

It's not in the current rulebook, and if it's not in the rulebook it's not a rule.

[SqHunter]

If there is no longer a rule on the drop or angle of the biluttstock, then you would think it would be more economical and easier to drop the pad rather than trying to match extra tall rings to a raised comb.

But I am worried that doing so would also put greater distance between the normal placement of the off hand relative to the forearm.

[acorneau]

If there is no longer a rule on the drop or angle of the biluttstock, then you would think it would be more economical and easier to drop the pad rather than trying to match extra tall rings to a raised comb.

But I am worried that doing so would also put greater distance between the normal placement of the off hand relative to the forearm.

Correct, it's all a trade-off.

If you look at the concept of the chin-gun it allowed for the gun to be dropped way down into a low hold with plenty of support-hand options, a low trigger hand/arm, and an upright head position, but you had to have a 4-5" riser to get the scope back up to your eye-line.

[No1_49er]

Apparently the jig doesn't matter anymore, is there still a maximum drop at heel?

It's not in the current rulebook, and if it's not in the rulebook it's not a rule.

I wish that this forum had a "LIKE" button.
It's so tiresome arguing about rules that are NOT in the rulebook.
We're still waiting for the next iteration of the NRA Silhouette Rifle Rule Book (last Revised January 2023) which is due out soon, apparently.

49er

[375Short]

2023 Rule book. The last sentence in 3.1d likely prevents just dropping the pad on a SB and HP stock.

[SqHunter]

Would anyone know how the current stock measurement rules were derived? Were they chosen to limit scores intentionally?

Or to put it another way, if the current rules were not to be considered, what is optimal stock design?