Underwood 220gr Hard Cast Pull-Down

The_Shadow · January 23 2014 03:25:32 PM MST

Cartridge is from Ammo Manufacture: Underwood 220gr Hard Cast (MT10mm)
Ballistics Information: 10mm Auto
Muzzle Velocity: 1240 fps
Muzzle Energy: 750 ft. lbs
Brass Make/Headstamp: Underwood - Brass
Bullet Make/Weight/Construction/Info; Length 0.7310"/Dia. 0.4010": 220gr. Hard Cast
MEPLAT 0.2640" / Flat Base
Actual weight 216.6 grains Crimp squeezed bullet to 0.4010"
C.O.A.L.: 1.2585"
Primer: Nickel color
Case: Diameter 0.4215" Crimp Diameter 0.4225" (Tight) Length 0.9880"
Powder Description/Positive ID/Type/Charge LongShot Weight: 8.6 grains

Intercooler · January 23 2014 06:47:32 PM MST

I have 8.4gr's from my box of 220's. Is that correct? These are before the "change" as well.

The_Shadow · January 23 2014 07:11:57 PM MST

Yea, 0.2 grains more than the previous load from you that we did. 0.2 is a lot at this level of performance! ${$default_shocked_smiley}$

Intercooler · January 23 2014 07:13:39 PM MST

It measured almost identical to mine on the Chronograph. The powder difference might not be giving much in the FPS gain.

Intercooler · January 23 2014 07:16:01 PM MST

I see Kevin's 220's are weighing 216gr's versus BB's 219gr's. Just something in the casting process?

mt10mm · January 23 2014 08:16:33 PM MST

My order from Kevin will be here tomorrow and I will get you a sample of the new loadings. Is the 8.6 loaded too hot?

Intercooler · January 23 2014 08:21:28 PM MST

That's a loaded question ${$default_grin_smiley}$

8.4-8.6 probably isn't something suited to cover the entire umbrella of all the platforms and how they are set up. Something along the lines of 8.0 and an even 1200 FPS would be fine I would think.

mt10mm · January 23 2014 08:23:26 PM MST

We will soon see what it's been backed down to.

The_Shadow · January 23 2014 08:31:59 PM MST

His older IMR800 loads were with 8.4 grains and the other round IC sent was at 8.4 grains LongShot. Whereas this one was 8.6 grains, 0.2 grains with this heavy weight/long bullet can spike the pressure up enough to causes the smiles you saw.

However, recoil setup and actual lock-up of the gun all play into whether the case stays inside the chamber long enough for the impulse of pressure to drop off before it starts the ejection cycle.

The_Shadow · February 06 2014 09:16:35 PM MST

Cartridge is from Ammo Manufacture: Underwood 220gr Hard Cast(reduced)(MT10mm)
Ballistics Information: 10mm Auto
Muzzle Velocity: 1200 fps
Muzzle Energy: 703 ft. lbs
Brass Make/Headstamp: Underwood - Brass
Bullet Make/Weight/Construction/Info; Length 0.7260"/Dia. 0.4010": 220gr. Hard Cast MEPLAT 0.2870" / Flat Base
Actual weight 216.4 grains Crimp squeezed bullet to 0.4010"
C.O.A.L.: 1.2535"
Primer: Nickel color
Case: Diameter 0.4215" Crimp Diameter 0.4230" (Tight) Length 0.9880"
Powder Description/Positive ID/Type/Charge LongShot Weight: 8.0 grains
Tested by Intercooler; EAA Limited 4.75" 1195, 1195, 1191, 1194, 1190, 1195. Average = 1193.3 FPS/ 696 LBS
EAA Hunter 6" 1254, 1221, 1215. Average = 1230 FPS/ 739 LBS

Made the change in velocity to reflect the reduced loading.

4949shooter · February 07 2014 03:33:56 PM MST

Still using Longshot I see. If these test out well they might be my woods load when I retire.

Intercooler · February 07 2014 03:51:22 PM MST

Quote from: 4949shooter on February 07 2014 03:33:56 PM MST
Still using Longshot I see. If these test out well they might be my woods load when I retire.

Test out well? You mean if they will work in a Glock okay?

4949shooter · February 08 2014 03:50:52 AM MST

Quote from: Intercooler on February 07 2014 03:51:22 PM MST
Quote from: 4949shooter on February 07 2014 03:33:56 PM MST
Still using Longshot I see. If these test out well they might be my woods load when I retire.
Test out well? You mean if they will work in a Glock okay?

Yes, for feed reliability as well as pressure issues.

As far as pressure goes I think they will be okay, but there are some more knowledgeable than me in this area who believe the velocity may still be too high for this weight/length bullet.

Actually, I almost ordered some of this last night to test in my Glock, but I held off because the Lone Wolf Tac length barrel is on back order. That, and I have the XDs in .45 coming, and I am thinking of picking up some more hollowpoints for it for off duty carry.

Intercooler · February 08 2014 04:51:35 AM MST

Unless it's a crap barrel/setup the pressure signs won't be any worse than the other Underwood weights or "Heavy" 10mm ammos out there. As for the function I sold my Dan Wesson 1911 because it wouldn't run 220's perfectly. Possibly if I had the barrel reamed or loosened some it would have but when the others ran it just fine that left it odd man out ${$default_wink_smiley}$

4949shooter · February 08 2014 05:58:36 AM MST

Any 1911 can be finicky with certain types of ammo, different magazines, etc. You have to be a real 1911 fan to run them. I am keeping my two Combat Commanders though. ${$default_cool_smiley}$

I am not trying to be skeptical about the UW 220's, but until I see their track record and test them in my gun I won't know for sure. If the 220's are loaded to the same quality as thee 165 tmj from Underwood I think they will be great! And this is what I am hoping for. ${$default_wink_smiley}$