Jediwarrior

A bull barrel significantly reduces recoil and muzzle flip. The added weight of the barrel absorbs recoil, which in turn allows you to use a lighter recoil spring. It does NOT reciprocate the full travel of the slide, it only moves back 1/4".

STI has been having issues with pistols with wrong timing. The VIS on the barrel have been machined, hence broken links and/or slide stops and/or barrel link pins. You may need to send the whole pistol back to have the barrel replaced. I've read that with new management, STI has corrected the problem. But I suspect that hundreds of pistols out there have timing problems.

I have seen more cracked Caspian slides than STI slides. I like STI slides coz they are harder than Caspian slides. Also, they seat lower into the frame so you get to use #2 to #4 barrel links. I have built more than 10 pistols using SVI slides, and so far they haven't cracked. They have very narrow rail widths, about 0.748 in. The barrel bore is oversize, about 0.705 in. You also have to use their firing pins and firing pin stops. They are slightly different than the standard ones.

I mill cut the slide if it is oversize by 0.002 in. I leave 0.0005 in. so I can use a sanding block to remove the tool marks. Same with the frame, I mill the sides of the rails and leave 0.0005 in. I use the Brownells slide rail micrometer and a regular outside micrometer. I have never used lapping compound.

#5-40 flat head screws Length is 3/8 inch.

Internal cuts are for Limited/Standard. Just didn't want to have holes on the side of the slide where the rear serrations are. I think external lightening cuts are allowed for Limited/Standard. Hope someone can chime in on this.

Aftec extractors are very inconsistent even the same batch and caliber. You have to file the body of the extractor facing the firing pin. Follow the radius on the body. You may also have to file the head, where it fits the firing pin stop. Forward the FPS, file inside facing the firing pin.

Hi Hotrodder, I use 3/16" diameter carbide end mill. Hi Bamboo, I remember guns from the Steel Challenge 20+ years ago with extra lightened slides like yours. This internal lightening is becoming popular again for Limited/Standard pistols.

Greetings, I would like to share pictures of rear internal slide lightening cuts using the plunge cut method. Early Colt Gold Cup and Commander slides use a side mill cut which doesn't remove as much material compared to plunge cut. Weight reduction is 30 grams. The theory behind this is that the less weight on the slide that travels over the wrist, the less muzzle flip. Used in combination with a tungsten sleeved barrel, which lightens the front of the slide, you have a faster cycling slide. Second picture shows a Colt Commander slide on the left. Extractors are installed in both slides.

It is normal for a regular bull barrel to rub at the 5 and 7 o'clock positions. I think the problem is the fillet radii on the sides of the rib on the SVI Hybrid barrel. The original Schuemann Hybrid barrels do not have a fillet radius on the sides of the rib. On the SVI, the radii, if not relieved, puts downward force on the barrel. This causes the bottom rub marks that you are seeing. I remove the radii on the sides on an SVI Hybrid barrel. I leave the rear radius alone. Do not touch the bottom part of the barrel. You need the support of the slide to prop up the barrel during cycling. Original SVI Sight Tracker pistols have material removed on the slide for clearance for the fillet radii on the rib. Some people like to do things the hard way.

Prior to Aug. 2012, they could not be imported into the US coz of patent. Frames and slides were originally made in Spain. Now, they are made in the Philippines. Barrel blanks are made in Spain. Small parts are MIM. I've met the owner and seen their factory in the Phils. Their consultant was a former STI employee from Texas. For the price, they're OK.

The patent expired 2 years ago, so SPS can now be imported into the U.S. SPS is based in Spain and was originally made there, but they put up a factory in the Philippines coz of lower labor cost. Frames were originally CNC machined from bar stock, but are now investment casted. Magazines are POS. I wouldn't buy one coz quality is hit or miss. They sponsor some top shooters in the Philippines like Jag Lejano, but his pistol only has an SPS frame.

Some single-stack 45 pistols come with ramped barrels, such as the SVI Infinity, and Kimber aluminium-framed pistols. I recommend non-ramped on the single stack 45 for most builds, but some customers insist on using ramped. I then tested a new build and experienced this damage on the frame and follower. So now, I have to tell the owner not to use CMC magazines.

Has anyone have any issues using a CMC Shooting Star 8-round 45 Auto magazine on a single-stack with a ramped barrel? I've seen one where the lower part of the follower gets caught between the barrel and frame after firing the last round. Severe damage to the frame and the follower would result, aside from the failure to hold open.

Yup, I've seen some of these lately. STI extractors are not MIM. Just hard and brittle.