P320 Lockwood Slide, 4.7” Bull Barrel

(5 customer reviews)


The Lockwood P320 Slide was designed by USPSA Grand Master Isaac Lockwood and the Grayguns team. This custom 4.7-inch bull barrel configuration features an aggressive texture and optimal mass balance for USPSA Carry Optics.

Includes custom slide, custom-designed and fitted 9mm bull barrel, Grayguns Guide Rod and Spring, and all internals. Options available will vary.

Photos shown may include a SIG Sauer® optic, which is not included. Ensure you read the full description below before ordering.

Looking for an optic or sights for your custom slide? Order your choice of optic or sight package and we'll professionally install the optic for free!
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Personally commissioned and designed by USPSA Grand Master Isaac Lockwood, this P320 slide is designed explicitly for Carry Optics and has the following features.

  • 4.7-inch full-size slide with optimal mass balance and aggressive texture
  • A custom Faxon bull barrel manufactured to Grayguns specifications and hand-fitted for the 4.7-inch slide length
  • Diamond-Like Carbon (DLC) or Bead-Blasted finish

We’ve provided a fast but very soft and flat shooter by balancing this particular combination of slide and barrel mass. The red dot tracks more consistently in the window for many who have tried this combination.

Design & Functionality

“Factory barrel-fit dimensions are dictated by the possible, wide dimensional extremes between FCUs and slides. Drop-in aftermarket barrels are reverse-designed from factory dimensions as a starting point and are thus even “looser.” As a result, you see a lot of pre-lock jams, failure-to-feeds and accuracy issues from barrels that may look pretty but don’t fit or shoot worth a hoot. Few P320s deliver the accuracy of which they are capable.

I designed our barrels to eliminate gross vertical slop when out of battery for reliable feeding and function. We individually fit each of our barrels to the slide it’s serialized, for a minimum clearance working fit in all axes. They group exceptionally well. In addition, our lockup values yield a softer recoil impulse and smooth sight return, with greatly enhanced durability. Nothing else available compares.”

Bruce Gray
President, Grayguns

Bruce Gray

Differences between the Lockwood and Modern Classic 4.7″ Bull Barrel Slides

In short, the primary difference is simple aesthetics, but Bruce Gray writes more about the slides in this post.

Package Includes

  • Custom Grayguns Isaac Lockwood designed slide
  • Grayguns Guide Rod with Recoil Spring
  • Custom Faxon bull barrel manufactured to Grayguns specifications
  • OEM internals (Ejector, Striker Assembly, and Slide Cap)
  • Choice of optic cut

Different P320 XFive Slght Plates

Lockwood P320 Slide – 4.7-inch – Additional Information

You can directly mount one of our red dot options to the slide. There is no need for an adaptor plate.

Our Grayguns Lockwood 4.7″ slides cut for the Romeo1 Pro have factory P320 XFive Legion optic cuts that will fit the newest adjustable rear sight plate, an OEM feature of the P320 XFive Legion pistol.

SIG changed the design of the sight plates when they introduced the P320 XFive Legion. Our slide cut for the Romeo1 Pro will only fit the XFive Legion adjustable rear sight base. Components can be mixed and matched, so you must check your slide and sight plate. Our Romeo1 Pro slides will fit the plate shown on the left.

The FTP Alpha 3 will not fit our slides. Although the hole pattern is the same as a Romeo3 Max, the footprint of the FTP optic is too long.

Additional information

Weight N/A
Dimensions N/A
Slide Configuration

DLC Finish, Cut for Romeo3 Max, DLC Finish, Cut for Romeo1 Pro, DLC Finish, Cut for Trijicon RMR, DLC Finish, Cut for Aimpoint ACRO P-2, Bead Blast Finish, Cut for Romeo3 Max, Bead Blast Finish, Cut for Trijicon RMR

Share your thoughts!

5 out of 5 stars

5 reviews

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What others are saying

  1. Aaron Bush

    Lockwood top end

    Aaron Bush (verified owner)

    I couldn’t be happier with this top end! Previously I have been shooting a custom X5 Legion that really performed well but this is an improvement in every way. The gun shoots flat and super soft but the real advantage this gun has is that the dot now returns so consistently it’s amazing. Where this top end really shines through is in two areas though, workmanship and accuracy. This isn’t just some slightly modified Sig product, fit finish and innovation really shine through. This is truly a custom piece of art!! Accuracy wise it’s hands down the most accurate semi auto I own, .80 groups at 30 yards is the norm. Thank you so much for a wonderful product.

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  2. Gary Crouch

    Lockwood slide

    Gary Crouch (verified owner)

    Ive had it about 2 weeks on top of a Max model. It does everything Grayguns said it does. So far the tightest group is about a quarter size at 20 yds but thats just me. I have called shots and i hit exactly where i aimed. I feel it would shoot a nickel at 20 yds if i could hold it. I haven’t had a malfunction and it cycles well with great dot return. It makes me wish i had done a complete GG custom gun from the beginning. A big thanks to Bruce and the guys for this one.

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  3. One person found this helpful

    Perfect for USPSA

    lamen.robert (verified owner)

    Absolutely in love with this slide and barrel. My X5 was opening up to almost 4” groups at 20 yards. I’ve been able to hit 1.5” groups at 20 yards freestyle with ease. The 4.7 length also pulls some of the weight off the front end which I find much easier to transition with speed.

    I have paired this with a full length Armory Craft AXG grip and Lok brass grip panels. This has moved all of the balance towards the trigger guard making it less front heavy like my X5 legion setup was.

    This upper assembly is so beautifully done. The quality is top notch, and the workmanship is unmatched. Well valued investment!

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  4. rascher5200

    Lockwood slide

    rascher5200 (verified owner)

    I received the slide last week. I installed the Romeo 3 Max and zeroed it yesterday. I was amazed at the groups i received during the zeroing process. At 10 yards, all shots were on top of each other. At 15 yards, all shots were within 1/2 inch and at 25 yards I had 1-1.5 inch groups.

    I then proceeded and did my normal practice. I run many drills at speed and was amazed how quickly the gun returned to my aiming spot. The overall balance was great. So far, the slide has exceeded my expectations.

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  5. jed.glosser

    P320 Lockwood Slide

    jed.glosser (verified owner)

    I want to compliment GrayGuns on their outstanding slide, I don’t shoot competition but I have done extensive testing with their Lockwood slides and I have found exceptional accuracy with them. I test them at 50 yards shooting off a bench with a Ransom Multi Cal rest, not the mechanical master rest. I shoot mostly 5rd groups and I have shot several under 1 inch groups. For example i took the avg of 17 groups the other day and it was 1.69” and I know ok that’s 5 shots but I am disappointed if I don’t shoot 1.5” group, they are that accurate for me and I finished my testing today with a 10 shot group and I measured it at 1.39” . I reload my own ammo and it makes a big difference over most factory ammunition but these Slides just simply shoot Amazing! Thanks Gray Guns, Jed

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Many parts sold by Grayguns - including but not limited to triggers, trigger kits, internal components and spring kits - are intended for installation by a qualified armorer or gunsmith who is familiar with the firearm.

Although kits fit with no issues in a great majority of pistols, Grayguns cannot guarantee perfect functionality in every instance.

Due to varying tolerances present in all mass-produced firearms, professional fitting by a qualified armorer who is familiar with the pistol's action may be required.

Grayguns offers installation services for all parts kits we offer. If you have any issues or questions about the installation process, STOP IMMEDIATELY and contact the Grayguns Customer Service Team.