Underwood 220gr HC

[edhead35]

This morning I shot my newly built up G20 for hunting. It is a gen 3 G20, polished internal trigger parts, "-" connector, KKM 6" bbl, L&M Precision Gunworks mounted RMR 3.25 MOA, Wolff guide rod and springs.

I shot 50 rounds of Undwerwood  220gr hardcast from 3 different magazines. In total I had 5 FTF's. All 5 were in the same magazine, and it fed most of the way, but didnt totally lock into battery. I used only the Wolff 24# spring, which flung brass 15-25 ft away.

Another oddball thing, about 50% of the time across all 3 magazines, before the last round would load, the slide would lock open. The round was never stripped from the mag, and the slide lock engaged. Any ideas what would cause this?

Accuracy was crazy. Same hole, over and over again from a rest at 50 ft.

[edhead35]

I also had 1 round that recoiled significantly less, and was alot quieter, but it didnt squib when I checked the bbl after field stripping.

[edhead35]

Also, a couple light primer strikes related to the ftf's.

[The_Shadow]

There have been quite a few reports with the Wide  Nose Flat Points not feeding completely in the G-20's and not just Underwood...I think it has to do with the angle of feeding and the bullets nose shape as the rear of the cartridge is being lifted as the slide returns to battery.  I think I read where DT shortened the COAL to 1.242" to improve feed and function.  I don't know what COAL Underwood is loading to with his stuff.

Sometimes with the stronger recoil spring if there isn't enough slide velocity and/or travel to the rear a round may pop up to the top of the magazine, to be stripped by the recoil energy.  Using less spring may help, letting the slide travel all the way to the rear long enough to have the cartridge pop up into position and be pushed forward by the slide to chamber.

Check out the info contained at this link...http://www.38super.net/Pages/Overall%20Length.html

Good luck!

[Yondering]

I don't think the recoil spring is too strong, with the symptoms edhead35 described, and especially not with this load. Failure to completely go into battery is more likely a weak recoil spring (not in this case), or tight fit of the round in the chamber, either because of fouling, oversized ammo dimensions, or tight chamber.

The slide locking back is probably a combination of recoil and one of your thumbs hitting the slide stop lever.

A tangent or secant ogive on the bullet nose would be better for feeding than the TC shape though.

[harrygunner]

Received my order of Underwood 220gr hard cast.

I've attached a photo with a Double Tap 215gr hard cast round. The DT round is on the left.

The metplate is larger on the DT bullet. Don't know if it shows, the UW bullet is a medium gray color. The UW bullet may be denser since it looks a tiny bit smaller than the DT bullet.

The UW box rates it at 1200 ft/s.  Intercooler recorded one of my DT 215gr at 1201 ft/s from his Witness.

What do you think?


BTW, guests (not logged in) will see no indication there's an attachment.

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[Intercooler]

   Good question. When I spoke to Kevin he said the wider nose could create issues in some platforms. I guess whichever one works best in your platform is the one to go with.

  The 215gr I tested looks discontinued by DoubleTap. I only see a 200gr. @ $48.19/50 and a 230gr. @ $48.19/50.

  Underwood has the 220's for $33.00/50.

I searched around and found many use the Rimrock Hard Cast bullets.

[harrygunner]

By appearance, the Underwood rounds will feed well. The DT, with its larger metplate, feeds 100% in both my Glock and 1911.

In reference to the 215gr DT, it was available some time between 2005 and 2007.  That's one of the rounds I mailed you this April. DT dropped that weight around 2007.

I'll be chronographing the Underwood rounds.

[Intercooler]

I'm trying to see how far the Gel can be extended out for testing. If he can get like 32" I want to send him a couple Hard Cast 220's to see just how far they travel. You think a piece of plywood or 2x4 in front would help tell us anything?

[Intercooler]

Other than the Gel being enough to hold the travel. Can you guys offer up some suggestions on how to set this test up? I'm sending chopinbloc some different ammos to try this week. I have never seen a Hard Cast Gel test so it has me interested.

[Intercooler]

I found one. If that little .380 goes 31" we need something to give us what we are looking for in using this 220 in the field.

[Yondering]

Depends a lot on the bullet, but you'll need a lot of gel to stop something like that Underwood 220gr.

For comparison: Using water filled milk jugs for an example, most hollow points won't penetrate more than 3-4 jugs (assuming they expand). In my testing, a mild non-expanding cast bullet will penetrate 12-14 jugs at least. In compact wet paper catalogs, where several good hollow point jacketed loads penetrated 6-8", my 215gr 10mm bullet at 1250 fps penetrated all 17" and was not recovered. The Lee 180gr TC bullet at 1300 fps penetrated 16".

[Intercooler]

Maybe Hard Cast just isn't worth testing. I'm sending at least one of the MFG's using the Zero HP and the MAC Razorbacks which I don't know what HP that is. Nobody has done Kevin's screaming 155gr. so sending that too and Cor-Bon 180gr BCSP.

[Yondering]

Maybe Hard Cast just isn't worth testing.

For gel testing of hard cast bullets, I recommend looking at the size of the wound channel, and just assuming the penetration is plenty deep enough. That way you don't have to worry about capturing the bullet, just set up enough gel blocks to tell you what you want to know.

[sqlbullet]

I agree with Yondering.  I have giving up on recovering hard cast bullets in most media.  They just keep going and going.