larryccf
Contributing member
YOU'LL need a few tools, first the receiver clamping shell to keep the receiver from moving in the vise - i lined it with some silicone self-fusing tape, no adhesive but increases the grip on the receiver
2nd, a decent barrel wrench - i made mine from a 2"x36"x3/4" bar of 4130 chromium-molybdenum alloy steel, I cut about a 5" of the bar off, then clamping the 5" pc on top of the 31" remaining pc, edge on edge, bored thru the two pcs at the same time for the two 3/8" grade 8 bolts. I went with a 31" handle length as the last 1/8 of a turn on the barrel is a b***h and i wanted to be able to control it easily, in lining up the two rods
two straight 1/4" square rods, 7 - 8" in length. the rear side of one straight edge i painted white and i used that one on the front sight /gas block - it makes it easier to see if you're perfectly lined up when the black rear rod has totaly block the front straight edge or vice versa
The instructions are in the pdf attachment, and fairly fred flintstone written
I'd review the pictures first then read the instructions - they'll make more sense
When i watched the swiss army armourer do the barrel changeout, i realized what i had seen at the sig factory - a technician was at a granite table, or the table top was granite & about 4" thick, and there were openings on 6" squares, with the chamber end of a number of barrels protruding thru from underneath, and the technician was using a vertical dial indicator to measure how much barrel protruded thru the granite table surface, so he was basically quality controling the amount of barrel that would be threaded
anyway, if anything is not clear, ask away, if i can answer i will
2nd, a decent barrel wrench - i made mine from a 2"x36"x3/4" bar of 4130 chromium-molybdenum alloy steel, I cut about a 5" of the bar off, then clamping the 5" pc on top of the 31" remaining pc, edge on edge, bored thru the two pcs at the same time for the two 3/8" grade 8 bolts. I went with a 31" handle length as the last 1/8 of a turn on the barrel is a b***h and i wanted to be able to control it easily, in lining up the two rods
two straight 1/4" square rods, 7 - 8" in length. the rear side of one straight edge i painted white and i used that one on the front sight /gas block - it makes it easier to see if you're perfectly lined up when the black rear rod has totaly block the front straight edge or vice versa
The instructions are in the pdf attachment, and fairly fred flintstone written
I'd review the pictures first then read the instructions - they'll make more sense
When i watched the swiss army armourer do the barrel changeout, i realized what i had seen at the sig factory - a technician was at a granite table, or the table top was granite & about 4" thick, and there were openings on 6" squares, with the chamber end of a number of barrels protruding thru from underneath, and the technician was using a vertical dial indicator to measure how much barrel protruded thru the granite table surface, so he was basically quality controling the amount of barrel that would be threaded
anyway, if anything is not clear, ask away, if i can answer i will
Attachments
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1A SIG550 clamps opened showing red silicone self fusing tape - Copy.jpg -
2 SIG 550 bbl w wrench before removing.jpg -
#3 sig 551 bbl installation view from rear.jpg -
2A SIG550 bbl w wrench close up #2.jpg -
bbl wrench blueprint.pdf
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SIG 550 series barrel changeout procedure.pdf
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sig 551 bbl installation view from rear.jpg -
SIG 551 bbl installation view showing proper alignment.jpg
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