Mother load! Old Cor-Bon 135's, Winchester Silvertips

Intercooler · December 05 2013 09:27:57 AM MST

The Shadow,

Now that we are barking up the right tree... let's test it! Can you take one of the good powder reloads and introduce a couple drops of water? Assemble and give a couple shakes? In a month or so pull it down for inspection?

Intercooler · December 07 2013 05:45:59 AM MST

Did you want to try that experiment?

I took an average today ~265gr's. The window I established (although wide) is 257-273. Headed out now to see how they shoot.

The_Shadow · December 07 2013 08:04:24 AM MST

Yea it is hard to tell by weighing total cartridges...loads only varied from 7.0 -7.4 typical of powder dropped charges.
Where as the total cartridge weights vary even more than the total charge weights by 16 grains.
Bullets can vary as much if not more than 5 grains plus to even more depending on construction.
Cases can vary about 5 grains from the same make to even more if different makes and head stamps.

The Hodgdon book shows a Sierra 180 JHC with 7.1 as 1150 fps at 35,600 psi
Speer 12 shows their 180 grain TMJ & GD with 7.5 as 1120 fps
Lyman Shows 175 gr SilverTip using 7.2 as 1129 fps

If the guy didn't make any stupid mistakes you should be fine.

Intercooler · December 07 2013 09:39:35 AM MST

I'm back and all is well. Took two boxes of 40 rounds and shot both ${$default_shocked_smiley}$ As a precaution I used my Glock approved gloves on the reloads ${$default_grin_smiley}$ Not a single malfunction, etc... using the Pro and 1006 platforms.

EAA Limited Pro 4.75" 1100, 1113, 1120, 1127, 1133, 1117, 1107, 1114, 1103. Average = 1114.8 FPS/ 497 LBS Not bad for punching paper.
S&W 1006 5" 1058, 1056, 1063, 1065, 1057, 1077, 1089. Average = 1066.42 FPS/ 455 LBS I can never understand why a 1/4" longer barrel gives less velocity.

So it looks like I have plenty of target ammo for a while.

The_Shadow · December 07 2013 12:32:04 PM MST

Seems they did OK! The S&W barrel must be a different fit with the conventional rifling! Number of lands & grooves? ${$default_huh_smiley}$

If you find any that give you issues for chambering, sent it for investigation! ${$default_roll_eyes_smiley}$

Intercooler · December 07 2013 01:04:59 PM MST

When I don't shoot the 1006 for a while, the first couple shots make me realize how much I hate the trigger! ${$default_sad_smiley}$

The_Shadow · December 07 2013 01:29:08 PM MST

Those EAA's spoiled you! ${$default_roll_eyes_smiley}$
Yea S&W could have done a better job with the triggers, ${$default_embarrassed_smiley}$ if they would have they would still be in high demand.

Intercooler · December 07 2013 02:56:19 PM MST

I forgot to mention every primer was flattened like a pancake ${$default_shocked_smiley}$ None of the brass showed signs of pressure at all. This makes me wonder if that tight crimp pushes pressure back on the primer? That would be another interesting test with the reloads making a couple loose on the crimp.

The_Shadow · December 07 2013 03:56:59 PM MST

Even though the velocity is not that high the pressures may be up there. Yes the tighter crimps can affect the primers also.
Combination of the two, faster powder and tighter crimp...Don't know what primers were used? Maybe Standard or Magnum, if magnum? That would bring pressures up some more.

Geeman · December 08 2013 06:59:52 AM MST

Quote from: Intercooler on December 07 2013 09:39:35 AM MST
I can never understand why a 1/4" longer barrel gives less velocity.

Its likly the chamber is tighter in the EAA than the S&W. A looser chamber is extra volume for the gasses to expand into, and that lowers chamber pressure.

Greg

The_Shadow · December 08 2013 09:37:19 AM MST

Geeman maybe you could run the numbers in QuickLoads for these for Intercooler.

180 grain FMJ (Bullet Make/Weight/Construction/Info; Length 0.6090"/Dia. 0.4000") Crimp Diameter 0.3860" - 0.3840"
Cases were mixed (Winchester and Midway) seating depth was C.O.A.L.: 1.2615" / 1.2670" / 1.2645" / 1.2640" / 1.2685"
Winchester WSF 7.3 grains,
Actual weights on the 5 I took apart 7.0 / 7.2 / 7.4 / 7.4 / 7.2
Velocity at 1120 fps
At 7.1 Hodgdon says 35,600 psi for a 180gr JHC

I have a feeling this powder is topping out very fast, not yielding velocity for the given pressures. Very Short duration peak.

Geeman · December 08 2013 10:51:46 AM MST

Sorry,

That powder is MIA in quickload ${$default_angry_smiley}$ .

Greg

The_Shadow · December 08 2013 12:05:43 PM MST

Oh well we have a saying for that down here in Louisiana! cest la vie = "Such is life" ${$default_cool_smiley}$

Intercooler · December 14 2013 11:11:33 AM MST

Fired one more box of 40 today and had one dud. I tried multiple times but the primer just wouldn't set it off!

EAA Pro 4.75" 1150, 1139, 1100, 1137. Average = 1131.5 FPS/ 512 LBS

In the fudge factor from the last time out.

The_Shadow · December 14 2013 02:21:59 PM MST

The things that come to mind are spent primer was either missed or put back into the casing. Contaminated primer (given the yellowish powder seen it could be related to moisture in the casing and it killed the primer) or bad primer are also likely! Stuff does happen...be glad to take it apart for a look see! ${$default_wink_smiley}$