Do you tune ammo to the gun or the gun to the ammo?!?

[Stjs45]

I know its a screwy question, but I have many times wondered what the proper load development should be!

 

The questions is: I have a STI Steel and was hoping to shoot around 1,000 FPS. I loaded the ammo for 950 , 1000 , 1050 , 1075.  Pushing  115 Blue bullets and Titegroup. Obviously 950 felt amazing but would not cycle reliable, not even close. When I say reliable I mean, a few didn't get fully ejected and stuck between slide and sight block. 1050 was the most reliable although still had one not fully ejected. 1075 was perfect 25 for 25.

 

Should I set the desired FPS (recoil) and play with springs, slide cuts, breaking gun it,  etc... or just suck it up and shoot what the "stock" pistol will cycle efficiently the way the manufacture intended it?

 

**STEEL CHALLENGE ONLY

Edited July 1, 2020 by Stjs45

[echotango]

First thing. Wrong powder. Even for steel challenge. Comps do work in minor. I would also say wrong bullet but coated fanboys will chime in. I'd switch to a jacketed bullet. 

Otherwise just shoot a SS with an optic.

 

Try wac, hs6, etc. 

Edited July 1, 2020 by echotango

[Stjs45]

17 minutes ago, echotango said:

First thing. Wrong powder. I would also say wrong bullet but coated fanboys will chime in. I'd switch to jacketed bullet. 

 

Try wac, hs6, etc. 

 

I tried Shooters World Major Pistol as I use it for my Major gun thinking I could get more gas out of it but it was very dirty and would not even load the bullet property there was soo much "corn flakes" in the chamber. It was ridiculously slow. got like 400fps out of 3.5 gn and 650 out of 3.8. I figured a slow powder was not burning right with such small load. 

I shoot coated bullets because I wanted something different than my major gun. I didn't want to ever mix them and shoot major in minor or vise versa.

 

I have WAC and could definitely try it. What grains would you recommend? Would you still change to 7# spring to a 6# to get a lighter load?

[echotango]

I ran 5.4gr wac w/115 MG and a 7# in my minor gun. 6 sometimes doesn't strip the next round. 

 

Too slow of powder and it won't burn all the way and is messy as you experienced. 

Edited July 1, 2020 by echotango

[Joe4d]

Well to your OP,,,, depends on the situation.
My SS 9mm , Para 1640 and SS 40 I tuned to the ammo cause I traveled alot where I couldnt reload. Sooo I tuned my 40's to American Eagle 165's and then made my reloads match that. My 9's were always set up to run Win WB 115's.

[Dwbsig]

I’ve had good results with 4.4 grs of sport Pistol / aa#2 with 124 gr delta p. out of my open gun for steel challenge . 

[Guy Neill]

Develop a load first that is reliable and accurate in the gun.

 

Then, if you want, modify the gun to better "fit" you.

[barry]

Gun must run 100%. All small adjustments to load or gun after that feel different for the first few shots then your still the same flawed shooter you were with the old gun setup or load. Practice practice practice.

[zzt]

You tune both.  Also, you used waaaay too little SWMP in your test loads.  For example, my steel load is 7.0gr 3N38 under a 115 JHP.  I would need just under 8gr of SWMP to make the same 138 PF.  I use SWMP for major.  When the last 9 lbs. of 3N38 is used I'll me using SWMP ( or AA7 ) for everything Open.

[MemphisMechanic]

Also, yes. You should definitely be expecting to change recoil springs in this gun when you switch between major and minor.

 

And, OP, are you ever going to shoot major PF through this gun? If not, that’s going to change their advice a great deal.

[Stjs45]

Btw. WAC was dirty, and felt snappier at 1120 fps ( 5.9 gran) @129pf    than the Titegroup (3.9grn) at 1060 and 122pf.  Titegroup would come back down to zero, while WAC pulled the dot off the top. 
 

both did not run 100%. The slide is not opening up all the way making the round get stuck and not going back into battery. I need to either drop a spring size to a 6# or add .2 grains of powder. As of now I’m going to run Titegroup as well as try to MG bullets, see if that changes anything. 

Edited July 3, 2020 by Stjs45

[zzt]

8 hours ago, Stjs45 said:

both did not run 100%. The slide is not opening up all the way making the round get stuck and not going back into battery. I need to either drop a spring size to a 6# or add .2 grains of powder.

 

If you want to stick with the wimpy loads, you can tune your gun for them.  I'd caution against going to a 6 lb. recoil spring.  It will cause problems.  The simplest thing to do is change your mainspring out for a 19 lb. spring, and increase the radius on the firing pin stop so it goes right up to the firing pin hole.  Gripping the gun tighter will also help.  You can go down to a 17 lb. mainspring and still light any primer.  If that doesn't do the trick you can lighten the slide or add PF.  

 

If you want the comp to actually work, you'll need to be in the 140-150 PF range with WAC.  You 129 PF load had more muzzle rise because you didn't make enough gas for the comp to 'work' (mitigate recoil and muzzle rise).  If you don't care you are better off using smaller amounts of a faster powder.  Titegroup will work fine, but would not be my first choice with coated bullets.  I'd use Sport Pistol or e3.

[Whoops!]

As has been alluded to - Major is a bad powder for minor loads.  Way too much unburnt powder, which, in my experience, actually does cause reliability issues.

 

As for the tuning question - Use the lightest recoil spring that you can tune your gun for - (it’s possible to tune a 2011 to use a recoil spring that is lighter than 6 pounds, but you have to put in the work).  
 

Use the lightest hammer spring that sets off your ammo.

 

Use the slowest powder that burns consistently in your open gun.

 

Work the load up around minimums.

 

 

The manufacturer never really tuned your gun - they put in a combination of springs that worked most often with factory ammo when their manufacturing tolerances were taken into account.

 

There’s a lot of progress to be made on an individual platform that a manufacturer can’t make on every gun sold.

 

 

 

Edited July 3, 2020 by Whoops!

[Dranoel]

I tune my pistols to a "range" of ammo I want to use. For example: In my ,45s I don't like shooting anything heavier than 185 gr. and usually shoot 152-155 gr LSWC or 160 gr HB PSWC. So my .45s are sprung a little lighter. I can still shoot 230 gr if I need to but I avoid it like the plague.  From there I tune the loads to their best accuracy in my pistols. That can be tricky as different barrel brands and lengths can effect how a given load works. One may like WW231 or Unique but not AA5 or AA7, while another is just the opposite.

[NOSHMJ]

I have the DVC steel, and run it reliably with a Blue 147 under 4.0 grn of power pistol.  Super light.