Walther Forums banner
Cancel

Jarvis Conversion Barrel .40 cal to 9mm

1217 Views 12 Replies 6 Participants Last post by  balance, 
J
Hand Gesture Finger Wood Nail

Joint Hand Arm Shoulder Sleeve

Bumper Automotive tire Rim Gas Automotive design

Sensitive content, not recommended for those under 18
Show Content
Eyebrow Eyelash Jaw Neck Finger

Gesture Finger Thumb Wood Nail

Finger Cosmetics Tints and shades Nail Thumb

I converted my Gen 1 P99 .40 cal to 9mm. The barrel functioned almost flawless for 50 rounds 115 gr and 150 rounds 130 gr. Half the rounds were in the OEM spring and half were in a DPM spring system. I did have one failure to return to battery. It jammed up pretty good, but I was finally able to rack the slide and eject the live Federal American Eagle 130 gr round. Funny enough, the failure happened during the OEM spring. The DPM spring was flawless. Mind you the spring was the longest spring so I did receive some brass in the face area and on top of my hat, but flawless function none the less.

Overall, I would recommend the Jarvis barrel. The fit is very tight and the rubbing is obviously noticeable after 200 rounds. I did not send in my slide for fitting. My question to the forum here is: Will this rubbing or friction damage my original slide in any way?

If you have any questions let me know.
See less See more
6
Reply
Save
Like
  • Like
Reactions: 1
1 - 1 of 13 Posts
B
JonP99 said:
Ammo or spring?
Click to expand...
Slide weight, and ammo and spring.

The .40 P99 uses the same recoil spring as the 9mm P99. They made to slide heavier to compensate for the more powerful round. This pistol will probably never be as inherently reliable as a 9mm pistol with this barrel (being heavier than even the .40 barrel), with the slide being heavier than the 9mm slide, and with the extractor, ejector, and breechface not being the optimal size, shape, and in the optimal placement and position for the 9mm round.

I'd imagine that if the manufacturers of these pistols could make pistols that were just as reliable with just a barrel swap and magazines, that there wouldn't be anymore design differences for the 9mm and .40 models.
Reply
Save
Like
1 - 1 of 13 Posts
Walther Forums
A forum community dedicated to Walther firearm owners and enthusiasts. Come join the discussion about performance, gunsmithing, troubleshooting, reviews, accessories, classifieds, and more!
Full Forum Listing
Explore Our Forums
PP and TP Series PPQ P99 PPS Free Range Time
Top