ICFRA FTR chamber spec rule

Discussion in 'Competition Forum (All Calibers)' started by swc123, Dec 19, 2018.

  1. swc123

    swc123

    Joined:
    Mar 17, 2010
    Messages:
    31
    ICFRA FTR chamber spec rules limits the dimensions of the chamber to the maximum dimensions prescribed by SAAMI (and CIP). From previous threads on this forum, it is clear that smaller dimensions on the neck, web or throat (that is not smaller than the bullet diameter) is not a concern. Am I correct in assuming this establishes the intent/spirit of the rule: that is to prohibit an "improved" chamber with greater case capacity? Or am I missing something else? Please enlighten me.
     
  2. ScottyB

    ScottyB

    Joined:
    Jun 15, 2011
    Messages:
    135
    That was pretty much how we looked at it for the 2017 FCWC in Ottawa. We had a minimum headspace gauge made that only contacted at the shoulder datum and a SAAMI max dimension case gauge made to drop fired cases into.

    The logic was that the use of these two gauges effectively created a bracket that reasonably defined the max/min of a 308W.
     
    Taildrag15X likes this.
  3. XTR

    XTR

    Joined:
    May 15, 2011
    Messages:
    3,495
    There was some discussion of the neck clearance spec before he FCWC in 17(the SAAMI is .3442), but as Scotty notes above the Canadians didn't measure that for minimums.

    At least one past (possibly) present member of a US team (not F class) that shot in either NZ or AU (I forget) has noted that some of the team got .344 neck reamers for the exact reason that they were concerned that they would get measured and fail tech. (that's a long way to fly to get DQd on a tech spec)

    FWIW, my reamer is a .342. I don't worry about necks. In 8 yrs I've not split a neck yet.

    There are a whole lot of 308 shooters out there that will tell you that there isn't any reason to shoot with less than a .342 neck on a 308. That is a no turn demin for Lapua brass.

    As loaded 308s in Lapua run about .337 to .338 od, if you get a neck tighter than a .342 you are either going to have to shoot WW brass. (Loaded WW will run about .336 od) or turn all of your brass.

    Granted, there are a lot of shooters who do turn, but I'm not one of them. My rifles shoot as well as or better than most and I honestly can't see that turning would improve my targets at either mid range or long range.
     
  4. swc123

    swc123

    Joined:
    Mar 17, 2010
    Messages:
    31
    Been away for some time, thanks Scotty and XTR for your replies.

    So does everybody agree, that the reason for having chamber spec rules is to limit the maximum case dimension, translating into case capacity?
     
    savagedasher likes this.
  5. XTR

    XTR

    Joined:
    May 15, 2011
    Messages:
    3,495
    Sure, I think that's pretty obvious.

    The reasoning is that we are all running the same chambering. The chamber checkers are there to make sure someone isn't running some kind of blown out 308 to get more capacity or some other modified case.

    One of the things the Canadians were concerned with was someone changing the shoulder angle, something similar to an SLR to get a 308 with a 30* shoulder that would still chamber in a SAAMI chamber, that's why their go-gauge was made to the datum line minimum. So, if the capacity is the same but the demins aren't spec then it's still not legal.

    The NRA rule says:

    "A rifle limited to .223 Remington or .308 Winchester or their commercial and/or metrification equivalents. Chamber dimensions must not exceed the maximum SAAMI or CIP specifications. Bore, groove, and throat dimensions may be selected to suit bullets used. There is no restriction on bullet weight"

    F class rules start on page 67
     
  6. swc123

    swc123

    Joined:
    Mar 17, 2010
    Messages:
    31
    Thank you for that XTR, especially the quote of the NRA rule (which is similar to most countries and ICFRA rules).

    This causes a conundrum in my view, the intent of the rule is undeniably to limit the case dimension/case capacity by specifying the maximum case dimensions, but then in direct contradiction, allows "larger useable case volume" by not limiting throat dimensions with regard to the resulting maximum overall length of the loaded cartridge. Take for example a 230gr Berger Hybrid loaded to an AOL of 2.810" (the max SAAMI length) versus what is currently used/allowed(?) with longer throating, say for example an AOL of 3.150", 2 completely different animals, yet both are called .308Win.

    What gives?
     
  7. XTR

    XTR

    Joined:
    May 15, 2011
    Messages:
    3,495
    The limitation is on the case, not the OAL of the loaded cartridge, and the useable case volume for a 230 and a 155 is the same. One is just longer, the case volume hasn't changed.

    At some point in the game the F class founders either didn't consider or more likely decided that they didn't want F-TR to be limited to 156gr bullets like the Full Bore guys and modified the wording to allow any bullet. Now I'll grant you that at the time they did that the 175SMK was about the best 308 bullet out there. Berger didn't get the 185 on the market until the early 2000s. In the end the case capacity is what it is.

    A few yrs ago there were some ideas floated to limit bullet weight, but it didn't gain much traction. More rules just bog the system down, it just makes one more thing for the MD to have to check.

    There was a time in the history of Target Rifle competition where you had to shoot issued ammo.

    There is no conundrum, it's the ruleset we shoot with, and it's working pretty well. If you want to shoot F-TR get a reamer with a .170ish freebore and load 185s or 200s .015 off the lands and go to the range.
     
    kybountyhunter likes this.
  8. 6fatrat

    6fatrat SLING SHOOTER

    Joined:
    Dec 22, 2011
    Messages:
    282
    It is my understanding a number of years ago a US Palma team in England had their chambers checked with a dummy round. The test round wouldn't chamber because of undersize necks.
    The Brits had a proper size neck reamer and opened up the necks, or the rifles were disqualified.
    Steve Bair
     
  9. XTR

    XTR

    Joined:
    May 15, 2011
    Messages:
    3,495
    Steve, I think that is the reason that we had the discussions well in advance before the 17 FCWC in Canada, and I hope that will continue in the future so that the teams and competitors don't get surprised. It would be a long flight back from South Africa if you got surprised and your chamber got you DQd. I know after the last round I have been making sure my smith cuts my new chambers .002 longer than SAAMI minimum. I have one chamber from before that discussion that is cut to minimum that my not have passed on the gauge test.

    I don't think I'd be too far wrong to guess that there aren't many (or any) guys with .344 necks on their reamers today. Most of the people I've talked to .342 is the norm.
     
  10. swc123

    swc123

    Joined:
    Mar 17, 2010
    Messages:
    31
    From previous posts and polls on this forum, there is a significant number of people who don't seem to mind to be limited to <156gr bullets like the Fullbore guys, maybe the Aussies have got it right with their F-Standard class after all.
     
  11. JohnKielly

    JohnKielly Australia, not Austria Silver $$ Contributor

    Joined:
    Oct 25, 2007
    Messages:
    941
    Don't forget the Canadians were shooting that class too until the ICFRA rules were formulated.
     
  12. Erud

    Erud Gold $$ Contributor

    Joined:
    Oct 31, 2008
    Messages:
    931
    Not really. It’s almost entirely a self-policing sport until you get to the very top levels of competition, and the vast majority of competitors will follow whatever rules are in place. The ones who won’t will find a way to cheat regardless of the rules. With a limited bullet weight rule, an MD wouldn’t need to check bullet weights any more than he needs to check to make sure F-TR shooters aren’t shooting 7-08 in necked down Palma brass in matches without the rule.

    I’d love to see bullet weight rules in place in US matches. I think the contest if shooting skill is way more interesting than the contest of ballistics.
     
    Taildrag15X, spclark, 6fatrat and 2 others like this.
  13. XTR

    XTR

    Joined:
    May 15, 2011
    Messages:
    3,495
    I don't think that F class is a ballistics competition on any level. In today's F-TR competition nearly all of the competitors run the same bullet (Berger 200.20x), a few run the 200 Hybrid, which is so close to the 20-x as to be almost identical, and fewer still run the 215Hyb, but the 215s at reasonable velocities are so near to the 200-20x that most of us don't find them worth the minimal increase (if any) in wind drift. There are some few shooters running the 185s, but not many. It took us a few yrs of development but I think we are approaching the limits of what can be done launching a bullet from a 308 case.

    I've experimented with high twist barrels and at least three of the high BC bullets out there today, and what I've found is that none of them will achieve the precision required for F -TR. You lose more points in the corners than you make up for with the higher BC. I do sometimes insist on doing things my own way, but I'm pretty sure I'm not the only person who has tried them, and as far as I know nobody was shooting them at Raton this yr. This is a case study in leave it alone and it will find it's balance point.

    If US Palma wants to implement a bullet restriction that's on them. I don't shoot Palma and have no idea what is going on there, but F-TR certainly doesn't need one.
     
    woodgrain, Dos XX, Medic505 and 4 others like this.
  14. savagedasher

    savagedasher

    Joined:
    Jul 25, 2012
    Messages:
    6,858
    Rules are only as good as they are police
    This is one that can work
     
  15. swc123

    swc123

    Joined:
    Mar 17, 2010
    Messages:
    31
    Any suggestions for a name for a possible new class, based on the original idea of F-TR, a Target Rifle (.308Win <156gr, .223Rem <81gr) with optic, fired from a rest?

    Something like:
    F-Fullbore?
    F-Palma?
    F-Standard?
     
  16. Warren Dean

    Warren Dean Team Savage

    Joined:
    Feb 23, 2014
    Messages:
    455
    It already has a name and it's not a new class....F-Standard. The Aussies still shoot it.
     
    spclark likes this.
  17. jsthntn247

    jsthntn247

    Joined:
    Mar 9, 2010
    Messages:
    1,628
    Just an FYI I tried some Alpha brass and my loaded rounds measure .334. I'm getting suut (spelling) down to the shoulder b/c necks aren't sealing off with a 342 chamber. Never had that with Lapua. If I was to keep shooting these I'd go with a 339 neck on the next barrel.
     
    Last edited: Jan 11, 2019
  18. Jdne5b

    Jdne5b Gold $$ Contributor

    Joined:
    Dec 20, 2011
    Messages:
    1,039
    Check that loaded round measurement. Typo? .334?
     
    Last edited: Jan 11, 2019
  19. jsthntn247

    jsthntn247

    Joined:
    Mar 9, 2010
    Messages:
    1,628
    Yes, you know what I meant. :)
     
    Jdne5b likes this.
  20. Jdne5b

    Jdne5b Gold $$ Contributor

    Joined:
    Dec 20, 2011
    Messages:
    1,039
    Irslow. Took me a min.
     

Share This Page