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Will a type 4 barrel fit on type 3 gun that has already upgraded forearm to type 4 ?
 

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Perazzi type III & IV are referring to forend attachment design only, not the receiver. Perazzi receivers went through at least 3 or 4 changes since the '60s. Some over lapping the period of forend changes, mostly only affecting stock inlays.

As long as the subject barrel matches the forend, it'll work on any receiver with proper fitting.

Barrel/forend to receiver fitting is a separate matter. It really depend on individual guns, you might get lucky, some just drop in, some require welding and re-cuctting.
 

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If you have already converted your type III to a type IV forend,I assume that you have also modified the angle of the locking bolt to match that of the type IV bbl. lugs?
If not, you may be facing some complex machining ... I have fitted a set of IV bbls to my type III Mirage, and in the process, discovered that IV's locking surfaces are cut to an 8 deg. angle, and III's are cut at 10 degs.

With an immense amount of generous guidance from Doug Braker, and access to a multi post Bridgeport mill and Thompson grinder ( accurate to a ten thousandth)with a machinist chum, we made the jigs, welded & recut, etc. ... not a trivial job.
 

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hi there , scott here sounds like you would know if a mx-8 skeet barrel would fit an mx-2000 an answer would be greatly appreciated, aske someone else and they were to busy to reply, thanking you in advance, scott
 

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hi there , scott here sounds like you would know if a mx-8 skeet barrel would fit an mx-2000 an answer would be greatly appreciated, aske someone else and they were to busy to reply, thanking you in advance, scott
 

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Very Interesting information. Would you be generous and post some photos of the jigs, they would be appreciated by many serious Perazzi aficionados. SteveB.
 

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Apologies to the OP for further stomping around in his thread, but it is relevant to consideration of type III/IV mods, and to sturgeons question.

Haven't any pics, but here's a thumbnail of the process we did - may not be correct, but it works.


The 80cm IV bbls were secured to the mills bed by a sliding, parallel vise, with the monobloc locked down by the water table flanges ( flares that sit on top of the receiver sides). The table was computer driven to the correct angle, and the locking tab extensions were given the lightest touch possible to assure both were equal and true. Then, my 70cm Tula type III bbl lugs were built up by TIG weld. This allowed them to be fitted in the mill and cut identically to the 80 cm bbls..
As the receivers locking block was a 10 deg type, it needed to be cut back to an angle just slightly less than the bbl lugs ( why? - when the gun is closed in battery, the locking piece slides both forward, and very slightly upward .... thereby taking up the 'lash' in the receivers channel) - this ~15 min. of angle corrects for that 'lash'.

To achieve this angle, and to be able to repeat it many times in the fitting process, we made a 'jig'. You knew I'd get to this part, right? ;).

A steel 'brick' of ~ 8"x4"wide x 2" thick was trued to a perfect rectangle, and then angled with a sine block set to allow a wedge to be cut across a top face - ie 4" wide with the down slope ~ 2". Then, one could drop the locking block into this wedge upside down such that the contact angles were facing upward and perfectly horizontal. A couple of holes punched & tapped allowed the bolt to be locked in place for subsequent cutting.

This jig w. bolt was presented to a precision grinder, and worked down to the correct angle. Next, it was a succession of removing the bolt and inserting into the receiver with the thumb lever and bbls ... and keep on grinding fractionally until the thumb/release lever sat at the wood/tang interface as in a new gun ....

Hope that's clear.

BTW, not having a type IV forend, it is a simple matter of cutting the type IV bbl lug back on the rear end to fit a type III forend - works like a charm.

Garth
 

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Sounds really complicated. Why not just swap locking bars? I thought that the different angle things were limited to MX3 not T3's but that could easily be a faulty ageing brain fart.

I have several T4 barrels fitted to T3 actions. Luchio did it with a file. Took maybe ten minutes a barrel tops. They lock up and function just great.
 

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Thank you very much for the detailed report, but I think the different lug/bolt angles were only on early MX-3.

Lucio, while he was with Perazzi USA, fit a type 4 MX-8 barrel with forearm to my old SC3 type 3 receiver, didn't have to change locking angles.
 
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