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Joined: Jun 2011
Posts: 35
Sidelock
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Sidelock
Joined: Jun 2011
Posts: 35 |
I'm tempted to buy my first SxS soon. I'm considering one of the Spanish makers, like AyA or Arrieta.
What are the nominal bore diameters that the Spanish gun makers are using, for their current production 12 bore and 20 bore guns? Are they .729 and .615 respectively, or are they underbored or overbored?
I'm mostly interested in the 20 bores and will use the gun for hunting (pheasant, quail, grouse) but I would consider a 12 bore as well as a strictly pheasant gun.
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Joined: Dec 2001
Posts: 12,743
Sidelock
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Sidelock
Joined: Dec 2001
Posts: 12,743 |
I don't know what Spanish makers consider "Standard". They will be marked in metrics. Metric equivelents in 12 & 20 gauges would be for a .729" - 18.5mm & for .615" - 15.6mm. You can look at the proofs & determine the amount & direction of deviation from there.
Miller/TN
I Didn't Say Everything I Said, Yogi Berra
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Joined: Mar 2005
Posts: 5,021
Sidelock
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Sidelock
Joined: Mar 2005
Posts: 5,021 |
I know the Spanish know how to regulate barrels and throw their patterns exceptionally well especially the two makers you mentioned. Good luck!!
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Joined: May 2010
Posts: 1,545 Likes: 106
Sidelock
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Sidelock
Joined: May 2010
Posts: 1,545 Likes: 106 |
Spanish as with Italian 20's tend to be bored at .626" . I dont have my conversion chart to hand but I bored a set of Spanish barrels on Friday and that was the equivolent marked size.
Most 12's come in between .720"/18.3mm and 728"/18.5mm , 18.4mm/.724" is the norm but as with any production there is a variance .
Does it matter ? Chokes should be based on bore size and a couple of thou either way will mke no diferance .
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Joined: Mar 2005
Posts: 5,021
Sidelock
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Sidelock
Joined: Mar 2005
Posts: 5,021 |
I agree Gunman why would it matter as long as the barrels are throwing the proper percentage pattern and correctly regulated.
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Joined: Jan 2009
Posts: 476 Likes: 76
Sidelock
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Sidelock
Joined: Jan 2009
Posts: 476 Likes: 76 |
I don't have a Spanish 12 or 20 but recently bought an Ugartechea 28 gauge. 28 gauge bores are supposed to be .550 inch and the bore gauge measured mine at .550 from the end of the forcing cone to the beginning of the chokes - dead nuts on the standard.
The choke markings are a different story. The right barrel is marked IC and it has .005 constriction - right at the open limit for IC (.004 is SK). The left barrel is marked M and it has .020 constriction - right at the tight limit of IM (.021 is F). I'll decide later, after I've shot the gun a good bit, if I'm going to have the right choke opened up.
I don't consider bore diameter to have any real relevance. Some of my guns are at minimum diameters and some have been reamed and have oversize bores. What is relevant is the bore to choke constriction relationship because it is the best indicator of what the actual choke is (actually shooting and counting pellets determines the actual choke but that's kinda hard to do in the store).
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