9mm Effect on Steel Question

[Low_Speed_Notper8or]

So I have been shooting some matches and have found some 115 grain 9mm, especially steel jacketed stuff doesnt always knock down steel.

Would a flat point, especially in a 147 grain bullet weight have better energy transfer against a steel target?

 

[RPZ]

Maybe hardcasts?

 

[swampcrawler]

My USPSA minor load (145gr Bayou Bullet at 900fps) reliably topples steel. Pepper poppers seem like they take half a day to fall sometimes, but one hit will drop them.

 

[wild willy]

Increasing the weight of the bullet will be the biggest help

 

[SharpDog]

So I have been shooting some matches and have found some 115 grain 9mm, especially steel jacketed stuff doesnt always knock down steel.

Would a flat point, especially in a 147 grain bullet weight have better energy transfer against a steel target?

You need momentum, not energy. Basically the heavier the bullet the better to knock down a steel plate. Also IMHO, a deforming bullet would be better than a hard cast. You should check out the Federal HST 147 +P Tactical as a benchmark.

 

[mcb]

More momentum is what you need. Either a heavier bullet or more velocity or both.

That said If you know you ammo does in fact makes the required Minor 125 pf the the problem may not be your ammo but that the steel is not calibrated correctly. At big matches there is an official way to challenge the calibration of falling steel. At my club matches we usually check all the steel with a minor gun before the match.

 

[RecoilRob]

The heavier slower bullet will almost always topple steel better than the faster and lighter one. An example used for many years is the closing of a heavy safe door: You can punch it with a strike (and bust your hand) or close it with a gentle (but longer) push using a single finger. The British used to believe that the heavy and slow bullets 'worked' on the target longer as they went through and there was some testing results that supported it. The USA adopted the 45 ACP after testing many calibers and bullet weights against cattle and other targets with the conclusion that they were more effective. I use a cast 147 (weighs about 154 lubed) and it smacks down steel better than anything I've found. There might be some advantage to the heavier lead bullets staying in contact longer too....but can't offer any proof. Try the heavier bullets for yourself and see how they work.

 

[someguy2800]

The heavier the better with steel. If you handload coated hard cast transfers alot of energy on steel. Soft jacketed bullets and faster bullets just splatter and send all there energy flying off at 90 degrees but bullets with a hard core seem to put more of it into the steel.

 

[mcb]

Knocking steel targets down is total a total momentum game plan and simple, heavy and slow or light and fast does not mater on a steel target. It is the product of the two. A soft lead/copper bullet's collision with a hard steel plate is as close to a perfectly inelastic collision as you can conveniently get. A 115 gr bullet at 1130 fps will impart the same amount of momentum to the target as a 147 gr bullet 884 fps. Bullet construction makes almost no difference if we are talking about lead and copper bullets. Things don't change until you have a bullets hard enough to bounce off the target (good for knocking down the steel bad for you and the spectators) or you are hitting the target hard enough to exceed the yield strength of the target.

If you know you ammo is making power factor and still not knocking down targets then it is a target calibration problem or you hitting it low/edges.

 

[Good Ol' Boy]

I will agree with everyone else on the mass of the bullet being better suited for the wanted task.

I shoot a fair amount of steel and the 230 from my 45 moves things around quite a bit more than the 115 from my 9, even though the 45 is moving 2-300fps slower.

 

[FL-NC]

9mm NATO seemed like it did well for me. Winchester ranger 124 grain ball.

 

[ATLDave]

Mcb is right about momentum being the relevant measurement. It’s “easier” to get that in pistols by increasing bullet weight in terms of keeping recoil manageable. Lots of 115 grain ammo doesn’t make minor PF, or is so close that a marginal hit won’t work.

Quality of the hit is another factor. Left-right centered hits at or above the center of percussion are most effective. Hits lower towards the pivot have less leverage. Hits off-center waste energy twisting the plate against the hinge and vibrating it. If you’re competing and going fast, it’s good to have PF to spare so that stuff doesn’t hurt you too often!