I'm ordering more Underwood Xtreme defenders because of their sale going on. My question is for my Shield 9mm, plus p or standard pressure. The standard is a 90 gr bullet moving at 1,400 pfs. I don't know if the extra 75 fps in plus p is worth the recoil and wear and tear on the gun for this application. Any thoughts?

I run HST 147 +P in mine but that’s going to feel different than the Underwood. Unless you’re running thousands of +P rounds through your gun, there is no measurable increase in wear and tear.

I may be mistaken but i thought manual says no +P in the shield

Pic shows the verbiage listed in my shield manual for reference.

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I practice with standard and carry +P.

Why did you select the 90 grain bullet?

Any special reason?

I don't own a Shield, but for my 9mm Glocks, I primarily train with standard pressure and carry +P, but I think it's important to run a fair amount of your carry ammo through your gun on occasion.

I believe the extra impulse from +P will help increase reliability if shooting from odd positions, moving or having a less than ideal grip which I think are realistic possibilities in actual defense scenarios.

this is why we train & practice. I would suggest getting involved in either IDPA or USPSA clubs in your area. You'll learn things you'd never get standing at a range in front of a target.

Sorry, but I'm not a fan of gun games nor am I much of an advocate of statically punching holes in paper.

I run standard pressure. I have some Federal HST Law Enforcement that I think is not labeled +P, but that stuff is hot.

Speaking of HST, ShootingTheBull410 on YouTube, tested a bunch of 9mm SD rounds out of a 3" SIG P938 including the standard and +P versions of 124 and 147gr HSTs. From his tests, the +P versions of the HSTs only gave 2-3% increase in velocity over the standard velocity.

ShootingTheBull410
- YouTube

HST is great ammo...if 9mm+P it will be marked.( see photo)

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S&W BG380, S&W 915 9mm

+P ist gute in the manual, +P+ ist verboten!

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Mike
μολὼν λαβέ

Federal 150g hst micro pistol. Low recoil. 850FPS, 15 inches penetration and .70 expansion. Doesn’t get any better than that.


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I thought so to.But latest on line test dont show the Micro 150 HST doing to good threw heavy cloth.Problem is the velocity was running to low.They should juice that round up.I have some (but unloaded it)I will stick with my 147 Ranger T or the 147+p HST i have.I will have to chrono the 150 out of my shield before i would trust it

Yeah, I know it would be marked. I just couldn't remember if it was +P or not. I usually run Hornady Critical Duty, but that HST LE caught me off guard. It seems way hotter than the Hornady.

Why do I go to the range to "punch" paper . So I can develop skill like a solid grip , shot placement , recoil management , trigger discipline , etc plus getting to know my firearms . As far as tactical training probably would help but I am old and slow so lol . I'm sorry but if you think you are going to buy a gun and only pick it up at the moment of need and be accurate , etc , well good luck with that . I use Federal 124 HST standard pressure defense ammo . I think Hornady is ok too loads of ballistic info out there on various ammo . Avoided + p stuff according manufacture suggestion .

The Shield manual states + P is ok but may accelerate wear; this is the standard S & W manual verbiage since the last century for 9 mm pistols.

To the OP's question, if your gun functions 100% with the standard load, you shoot it well and can afford to practice with it, I doubt the extra 75 fps is significant. Good luck in your decision.

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Alan
SWCA LM 2023, SWHF 220

I’ll be picking up a Shield soon and found this thread very helpful. Thanks for weighing in everyone.

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Old Cop
LEO (Ret.)

Interesting that Smith and Wesson's "Military and Police" line of pistols are not designed to handle a steady diet of NATO pressured rounds which is used by Military and Police around the world.

You would be correct. Standard loads such as the 124 gr. HST will give plenty of penetration in the standard velocity. +P is not needed and purely overkill IMO.

I practice with Speer Gold Dot reg.velocity and mix in some +p. I carry +p (Not the short bbl ammo version) in my Shield. I agree with MisterX on the reliability issue. The shield has a VERY strong recoil spring and mag spring. You might give some thought to your ammo choice. Most police/ feds carry a 147gr bullet because it will penetrate windshield glass etc.. A 124gr bullet will have slightly less recoil and (hopefully you won’t be shooting at cars) has good penetration. My opinion? (and everyone has one). A 90gr bullet is too light. Ok out of an AR rife. Do some research on this. Don’t take my word! Don’t make your defense ammo choice because of price. What is your life worth? Good luck. Be Safe.

Just FYI that 90 grains is at 1,400 fps rather than something much less velocity with more tradition 115 to 147 grain metal bullets.

I’m no bullet guru but wanted to point out this fact. In the rifle hunting world there are die hard advocates for heavy and slow bullets, and an eaual number of advocates for light and fast bullets. Who is right I do not know.

I recently got some standard pressure 124 grain HST. They seem to consistently shoot lower than my practice 115 grain Blazer brass and the Hornady critical defense 115 grain. Has anyone else find the HST to shoot low?

This bullet design is a sold copper projectile and the weight it comes in is 90 grains. That is the only option.


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They are. I called Smith and Wesson CS
And they said it’s rated for +P. I asked if it was limited use only or if they had any recommendations on use of it, he told me it’s rated for it and use it all I want.


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Not based on price. The ammo I’m asking about is $28 a box of 20. The penetration is far superior to 124 or 147 grain hollow points. If you are unfamiliar with the round go to you tube and search Underwood 9mm Xtreme Defender. The military arms channel did extensive testing on this round and it performed better than any leading hollow point in the test.


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Yes I have. All ammo shoots low in my shield except 147 grain bullets. They hit point of aim but lighter bullets shoot low.


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Does the underwood xtreme defender round not expand?

No it does not. It’s a fluted solid copper bullet that is barrier blind and doesn’t rely on expansion.


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I'm just wondering why you chose this round over a conventional hollow-point?

1. It doesn’t matter if it hits clothing, glass, metal or anything else. It still performs as designed and penetrates 15-18 inches.

2. My area has had some issues with protesters blocking roads and attacking people in their cars. If I ever had to fire through auto glass to protect my family I wanted a round that would stop the threat.

3. They feed very reliably.


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I was looking at trying the Polycase Interceptor ammo. Same idea of design. I guess when you get with this style bullet you not only feel shot but also screwed.

Balistic testing consistently shows +P ammo is not very effective in short barrelled guns, particualrly the Shield length. (Shorter thn 4"). It picks up little or no additional velocity as there is not enough time to utilize the additional powder in the +p round. At best it doesn't do anything, worst case, its louder and makes a bigher flash as the powder burns outside the barrel. Not my opinion, it's what the data in several tests shows. Lot's of data, this is just one recent article that addresses the question. 400 Bad Request Lucky Gunner has a ton of test data on the subject along with bunches of additonal tests by others.

The use of +P and/or NATO is more for cycle reliability than for increase in ballistics. 9MM NATO was designed to cycle in SMG which uses heavier internals than a pistol. The pistol just had to handle the slightly hotter round.

interesting, the 124 grain HST hit LOWER than the 115 grains do. I have not yet tried 147 grains. But it would seem like 147 would hit even lower yet. Why would a heavier bullet hit higher?That makes no sense to me.

I was surprised when I tried Federal 150 Micro and it shot significantly above POA. I couldn't find practice ammo with similar POA performance, so passed it up as my carry ammo. I did a lot of research and shot a bunch of loads based on that research. Ended up with HST 124gr as the POA was spot on with common white box 115gr ammo and the ballistic results are on par with several of the best rounds. Your experience may vary ��

Only shoot what you can practice with. I personally do not care for the displeasure of shooting +p through the shield. A couple of mags and you really start to feel it in your strong hand. I shoot 124 hst and carry 124 hst in the shield. As for my 2.0 compact I carry and shoot 124+p hst. I also purchased a few hundred rounds of the hornady critical defense light recoil to try in the shield but haven’t had time to see how she likes it.


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"Yes, lighter bullets have a slightly flatter trajectory. However this does not account for the differences in point of impact observed at self-defense distances with handguns."

"These differences are accounted for by internal ballistics. Very simply, recoil starts (and the barrel starts to rise) after the trigger is pulled. Lighter bullets accelerate more rapidly and exit the barrel sooner (i.e. have a shorter barrel transit time) in the recoil 'cycle' than heavier bullets. Thus, the barrel is pointing lower for lighter bullets, and higher for heavier bullets when they exit the barrel. This is oversimplified, but you get the idea. Even a lighter bullet, downloaded to the same velocity as a heavier bullet (and thus the same essential trajectory, or 'flatness') will shoot lower for this reason."

This accounts for lighter bullets shooting lower.
Thanks to: cosermann Grandmaster Post # 3
Why does a 125 gr bullet shoot lower than than a 158 gr bullet

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It's The Carbonaro Effect!

The standard 124gr HST or speer or whatever is just fine. So many people get hung up on +p and to be quite honest a short barrel sub compact isn't going to take advantage of the +.. just more recoil, more wear, and more $$. Its not needed. Testing on standard velocity HST 124gr is exceptional out of smaller guns and thats all thats needed. If you truly think you are going to be shooting thru car windows you could try the 135gr Hornady Critical duty. But again, i don't plan to shoot out car windows. don't waste your money on +p.

I understand the oversimplified summary explaination.

The only problem is that my experience is the exact opposite. The lighter bullets are hitting higher!

Here is a very good, defining article writen by: Chuck Hawks and Jim Fleck; Which I would not call an Over Simplification!

"The Effects of Bullet Weight, Velocity and Trajectory on Point of Impact"
The Effects of Bullet Weight, Velocity and Trajectory on Point of Impact

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It's The Carbonaro Effect!