bigman Posted April 29, 2012 Report Share Posted April 29, 2012 My gun is a fixed choke and was told when i brought it s/h that it was 1/4 3/4 , after cleaning it today iv noticed on the barrels it has IMP MOD# an FULL## so is there a way i can check for sure what i have Quote Link to comment Share on other sites More sharing options...
bedwards1966 Posted April 29, 2012 Report Share Posted April 29, 2012 A quick way is to measure it with a gauge such as this, or ask a RFD to do it. The most accurate way would be to pattern it. It's nice to know, but unless you need to know for shooting steel it makes very little difference. Quote Link to comment Share on other sites More sharing options...
wymberley Posted April 29, 2012 Report Share Posted April 29, 2012 Unfortunately, it is becoming increasingly obvious that there are certain individuals that are posting way beyond the capability of their brain to keep up. Bigman, a sensible question that you're right to ask. As you've had to, it's probably fair to say that you haven't got the proper kit to do it yourself. Whereas a pattern test is the ultimate answer (who's to say that the barrels haven't been 'fettled' since they were stamped), your local RFD/gunsmith will do it in a couple of seconds and if you're a regular customer (where did you get the gun?) he probably won't charge. If you get one of those gauges, would you let me have it as I use them for their intended purpose - fishing weights! Quote Link to comment Share on other sites More sharing options...
Graham M Posted April 29, 2012 Report Share Posted April 29, 2012 If you get one of those gauges, would you let me have it as I use them for their intended purpose - fishing weights! Unfortunately this is very true as those gauges are only of any use if you know for sure that your bore is a true .729. choke is measured by constriction. 10 thou of constriction is ¼ 20 thou of constriction is ½ 30 thou of constriction is ¾ 40 thou of constriction is full If the bore is .724 for instance and you use that gauge, and it shows ½ choke, then the real choke would be more like 5/8 due to the bore being 5 thou smaller thus making the constriction at the choke 5 thou less than if you were measuring a normal .729 12g. Conversely if your bore was slightly oversized with a bore of .734 then the choke would be @ 3/8 due to the constriction being 5 thou more. I'm off to lie down now as I have a headache. G.M. Quote Link to comment Share on other sites More sharing options...
bedwards1966 Posted April 29, 2012 Report Share Posted April 29, 2012 Unfortunately, it is becoming increasingly obvious that there are certain individuals that are posting way beyond the capability of their brain to keep up. That's not very nice. I told him that he could buy a gauge for it. I told him that a RFD could measure it. I told him how to find out accurately if he really wants to. I also pointed out that in many cases it's not that important to accurately know the choke, but I've explained how to, which is what was asked. Quote Link to comment Share on other sites More sharing options...
andy198712 Posted April 30, 2012 Report Share Posted April 30, 2012 Unfortunately this is very true as those gauges are only of any use if you know for sure that your bore is a true .729. choke is measured by constriction. 10 thou of constriction is ¼ 20 thou of constriction is ½ 30 thou of constriction is ¾ 40 thou of constriction is full If the bore is .724 for instance and you use that gauge, and it shows ½ choke, then the real choke would be more like 5/8 due to the bore being 5 thou smaller thus making the constriction at the choke 5 thou less than if you were measuring a normal .729 12g. Conversely if your bore was slightly oversized with a bore of .734 then the choke would be @ 3/8 due to the constriction being 5 thou more. I'm off to lie down now as I have a headache. G.M. this^ They use a bore gauge of such in the gunsmiths, had mine checked this week. its a long rod they poke down the barrel, twist the end so it expands in the bore, and measures the width, then slide it out and see what the taper or restriction is... simples very accurate piece of equipment though mine has FULL written on the barrel but had been opened out to half choke, but when measured it had a 13thou restriction, so in between a 1/4 and 2/4, nice happy medium hopefuly.... it was free and didnt take long, at my friend Local gun smiths Quote Link to comment Share on other sites More sharing options...
andy198712 Posted April 30, 2012 Report Share Posted April 30, 2012 http://www.brownells.com/.aspx/cid=11237/k=choke%20measuring%20tool/t=P/Products/Measuring-Tools or with that.... Quote Link to comment Share on other sites More sharing options...
andy198712 Posted April 30, 2012 Report Share Posted April 30, 2012 when someone asks what choke i have, i'll say.... 11/32th roughly Quote Link to comment Share on other sites More sharing options...
Guest cookoff013 Posted April 30, 2012 Report Share Posted April 30, 2012 best thing to do is get a smith to mesure the bore, and the choke, then you have a "extremely accurate" mesurement. if thats all you want, thats fine. then at some stage pattern it. Quote Link to comment Share on other sites More sharing options...
bigman Posted April 30, 2012 Author Report Share Posted April 30, 2012 (edited) best thing to do is get a smith to mesure the bore, and the choke, then you have a "extremely accurate" mesurement. if thats all you want, thats fine. then at some stage pattern it. thanks to all your replys guys , ill run it in the shop at the weekend and see if i can get in checked Edited April 30, 2012 by bigman Quote Link to comment Share on other sites More sharing options...
andy198712 Posted April 30, 2012 Report Share Posted April 30, 2012 nice one, he should tell you what the restriction is. Quote Link to comment Share on other sites More sharing options...
ChAoS Posted May 1, 2012 Report Share Posted May 1, 2012 Unfortunately this is very true as those gauges are only of any use if you know for sure that your bore is a true .729. Indeed. If you use a "fishingweight guage" on my barrel, it'll lead you to believe that's tightly choked. In fact, the manufacturer tells me that these barrels are TC *but* under-bored at .690" all the way down... (It's a slug gun.) Regards, Mark. Quote Link to comment Share on other sites More sharing options...
Graham M Posted May 1, 2012 Report Share Posted May 1, 2012 Indeed. If you use a "fishingweight guage" on my barrel, it'll lead you to believe that's tightly choked. In fact, the manufacturer tells me that these barrels are TC *but* under-bored at .690" all the way down... (It's a slug gun.) Regards, Mark. In which case the chokes would actually appear to be very open due to the fact that the restriction would be almost nil. G.M. Quote Link to comment Share on other sites More sharing options...
wj939 Posted May 1, 2012 Report Share Posted May 1, 2012 On the same note, multi chokes..... my beretta is mobil chokes, as is my friends, however the barrel diameters are both 0.1mm different, therefore im thinking that if the chokes are all interchangeable and made separate then a half in mine may not be the equivalent in his? Quote Link to comment Share on other sites More sharing options...
ChAoS Posted May 1, 2012 Report Share Posted May 1, 2012 In which case the chokes would actually appear to be very open due to the fact that the restriction would be almost nil. Sorry - I must've missed something, here. I couldn't actually follow the guage link and assumed that it cited the "stepped brass cylinder" type of guage. If you use one of those to measure the choke, it *appears* tightly choked (.730->.690) but it's really TC. (And, "yes", it has quite a wide pattern...) Regards, Mark. Quote Link to comment Share on other sites More sharing options...
Andy H Posted May 1, 2012 Report Share Posted May 1, 2012 (edited) On the same note, multi chokes..... my beretta is mobil chokes, as is my friends, however the barrel diameters are both 0.1mm different, therefore im thinking that if the chokes are all interchangeable and made separate then a half in mine may not be the equivalent in his? If you are going by what is stamped on the barrel , Then that measurement is the bore 9" from the breech face and not just before the choke. Edited May 1, 2012 by Andy H Quote Link to comment Share on other sites More sharing options...
wj939 Posted May 1, 2012 Report Share Posted May 1, 2012 But presumably the barrels wouldn't taper? Would they? I know some of the extra modern stuff does but I thought that this was basically just the tolerances they work to? Quote Link to comment Share on other sites More sharing options...
PhilR Posted May 1, 2012 Report Share Posted May 1, 2012 On the same note, multi chokes..... my beretta is mobil chokes, as is my friends, however the barrel diameters are both 0.1mm different, therefore im thinking that if the chokes are all interchangeable and made separate then a half in mine may not be the equivalent in his? I've got an old Beretta 687 mobil choked gun. My top barrel is stamped 18.4 and the bottom 18.3 and I had the same thoughts about choke constriction between one barrel and the other using the chokes supplied with the gun. However, I've had the bores measured exactly and the top is, working in thou of inch, .726" and the bottom .724" the .002" difference isn't going to make the slightest difference to what pattern the gun throws as there's a greater variance between each cartridge. The only way to satisfy youself regarding the pattern each choke is throwing is to test it on a pattern plate, as previously mentioned. Teague gives some info on different gun barrel dimensions and choke constrictions here: http://www.teagueprecisionchokesltd.co.uk/reference_chart.html I have noticed that the Beretta chokes when I've measured them actually don't correspond to the dimensions given in the chart, some are tighter and some are more open, that doesn't surprise me as they are mass produced. I've also got some Teague extended chokes and they measure exactly as the chart dimensions and these are what I prefer to use. Quote Link to comment Share on other sites More sharing options...
evo Posted May 1, 2012 Report Share Posted May 1, 2012 (edited) Unfortunately, it is becoming increasingly obvious that there are certain individuals that are posting way beyond the capability of their brain to keep up. Bigman, a sensible question that you're right to ask. As you've had to, it's probably fair to say that you haven't got the proper kit to do it yourself. Whereas a pattern test is the ultimate answer (who's to say that the barrels haven't been 'fettled' since they were stamped), your local RFD/gunsmith will do it in a couple of seconds and if you're a regular customer (where did you get the gun?) he probably won't charge. If you get one of those gauges, would you let me have it as I use them for their intended purpose - fishing weights! well said wymberley :good: i,m very surprised he hasnt been asked has he got a SGC quite amazed actually, :lol: i took mine to the gunsmiths at the clay ground it only took him 2 mins to tell me what they where and didn,t charge me either Edited May 1, 2012 by evo Quote Link to comment Share on other sites More sharing options...
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