My KeyHole is better than your KeyHole

[Ninering62]

I’m at my range with my .40 Omega today.
I’ve been messing with 200g SW’s to get to know my new gun up to this point.
Today I decided to send some 225g ST2P bullets downrange & run them through my chrony.
MV is avg in the 2830’s fps
BUT when I didn’t hit my 100yd target eith 3 shots, I switched to my 50yd “ free real estate target “ lol
And this lil shocker is what I saw. No wonder I didn’t hit the 100yd target huh.
Now that’s what I’d call “ Thee perfect KeyHole “!

 

[deermanok]

Cool

 

[illinoishunter]

Wow. That's pretty cool to see. Looks like you meant to do it.

 

[derfhunter]

I had that problem with the 200 gr shockwaves in my 40 but the 236 gr fury star tips work just fine for me

 

[Ninering62]

Wow. That's pretty cool to see. Looks like you meant to do it.

Yes, I was thinking the same thing; that I couldn't have made a more perfect keyhole if I tried. Now to figure out how to stop it. The 200g SW's shot like high dollar machined bullets, put them in a hole. Hopefully slowing them down some will stabilize these bullets. Though, IDK why they won't stabilize at 2800fps. They " should ".

 

[Ninering62]

I had that problem with the 200 gr shockwaves in my 40 but the 236 gr fury star tips work just fine for me

Just the opposite for me. The 200g SST/SW's shot in a hole at 2800+ but these 225g ST2P's are keyholing right out of the muzzle for them to impact completely sideways at 50yds. MUCH more testing to do....obviously.

 

[BigBoresmokepole]

Just the opposite for me. The 200g SST/SW's shot in a hole at 2800+ but these 225g ST2P's are keyholing right out of the muzzle for them to impact completely sideways at 50yds. MUCH more testing to do....obviously.

Good group is that bullit to bore I would get that sized a little tighter and go again good luck going down a new rabbit hole .

 

[Ninering62]

Good group is that bullit to bore I would get that sized a little tighter and go again good luck going down a new rabbit hole .

" Good Group " sir, would you like to borrow my glasses & have another look?
The POI was 6"Left x 4" Low from POA ^ they impacted perfectly sideways.
Yes, I'm shooting sized bullet to bore .40. I have approx 5lb of downforce to load. The 200g SW's & the 225g ST2P are sized the same.
Thanks, I'll knurl up a few bullets for a little tighter fit & see how that does. I'll drop my charges down some too & bring the avg MV into the 2600fps range & see if they stabilize there. If not, I'm off to another bullet. I have a cpl bags of 240g OT's which is what I built the gun to shoot, but I also saw that it should stabilize the 225g in the same velocity range as well. That clearly IS NOT the case!

 

[anonymouscowherd]

Found out the expensive way that almost 4k rounds thru a mini-14 mostly rapid fire will cause this at 10 yards

Shot at a VW Bug sized boulder in the middle of a large lake to see just how bad things were and missed it by 15 yards ...

 

[Slingingslugs]

Let's get ready to tumbleeeeee.....

 

[Ninering62]

Let's get ready to tumbleeeeee.....

Hilarious! And if you don't read that out loud in your best Michael Buffer voice, theres somethin wrong with ya

 

[JBushnell]

That's impressive!!!

 

[Ninering62]

That's impressive!!!

Thanks, ain't they the purdiest keyholes ya ever did see.

 

[Hausser1]

Yes, I was thinking the same thing; that I couldn't have made a more perfect keyhole if I tried. Now to figure out how to stop it. The 200g SW's shot like high dollar machined bullets, put them in a hole. Hopefully slowing them down some will stabilize these bullets. Though, IDK why they won't stabilize at 2800fps. They " should ".

perhaps these are those "Tumble on Impact" bullets?

 

[The long rider]

That bullet for some reason is not obturating properly. I see it is a .402 bullet, what size is it after you size it to the bore? Are you using the VV-N530 powder? I'd bet the jacket is thicker on that bullet than the 200 gr. shock waves you had success with. I would think you should size your bullets a little bigger so you have about 30 lb. of pressure on a bath scale and bump up the powder to get 3000 fps and get those bullets to obturate and fly straight.
Problems like this can be frustrating at times, but when you get it figured out it gives a great sense of accomplishment.
Just remember, experience is what you get, when you don't get what you want. Good luck on this mission.

 

[Ninering62]

That bullet for some reason is not obturating properly. I see it is a .402 bullet, what size is it after you size it to the bore? Are you using the VV-N530 powder? I'd bet the jacket is thicker on that bullet than the 200 gr. shock waves you had success with. I would think you should size your bullets a little bigger so you have about 30 lb. of pressure on a bath scale and bump up the powder to get 3000 fps and get those bullets to obturate and fly straight.
Problems like this can be frustrating at times, but when you get it figured out it gives a great sense of accomplishment.
Just remember, experience is what you get, when you don't get what you want. Good luck on this mission.

I’ve sized the bullets to give me 5lbs of downforce to load them. I was using IMR4895 powder.
I’ll bump these bullets up a little this morning & fire a cpl more to see what that does. Then I’ll switch to IMR3031 to see if that helps. I have N120 & N110 to test as well if the 3031 gives me ignition probs.
I got plenty of Acc2495 for the gun, but it’s insanely dirty & in only 5-6 shots I can’t get a bullet down the bore & the BP & vent liner get clogged. So I’m not going to use that anymore. I sure screwed up buying 4lbs of that powder.
I’ll get it figured out, I always do.

 

[The long rider]

The IMR 3031 should work well for you and give you lots of speed. Just remember that it's temperature sensitive and could loose 150fps when the temps drop which could play hell on your long range groups. IMR 4166 and IMR 8208 XBR would be a little better if you can find them. They should be a little easier to find than the VV-N 530 powder.

 

[Ninering62]

The IMR 3031 should work well for you and give you lots of speed. Just remember that it's temperature sensitive and could loose 150fps when the temps drop which could play hell on your long range groups. IMR 4166 and IMR 8208 XBR would be a little better if you can find them. They should be a little easier to find than the VV-N 530 powder.

Thanks for your post brother.
That does concern me with the 3031 bc of the constantly wide variation in ambient temps here.
I will track down the N530 & N130 to test out. I’ve become a fan of the V powders.
I’ll look for the other two IMR powders too when I get some more funds.
I am looking forward to a bunch of load testing in this gun.

 

[bronko220002]

The .40s alwYs intrigued me but being from PA I can't use one for hunting. Not even in the general hunting season. Muzzleloaders must be .44 cal or larger (pistols .50 or larger).
I believe these regs have been made up from input by traditionalist. There is no doubt in my mind that a .40 can kill a deer or black bear. What gets me is you can use a .45 muzzleloader and a .40 cal bullet in a sabot ut not a .40 cal muzzy! Makes no sense.
IMO the rule should be changed to address bullet diameter and not bore.

 

[The long rider]

I know you already know this, but it's worth saying again,
When you make an adjustment on your die and the bullet needs more pressure to push down the tube, be sure and drop your charge by 10% or more just to be safe.
The .40 builds pressure like crazy fast! Let your chrony be your guide. Every bullet is different. I believe the bearing surface of the bullet plays a big role in pressure. The 240 gr.Fury 401 OT bullet will build more pressure than a Pittman 225 or 250 grain Accumax bullet in my gun I dropped 4 grains of powder using the Fury 240 gr. compared to the Pittman and still @ 3050fps.