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I am loading Mastercast 200gr LSWC to make major pwr factor. I am using clays pwdr but may change depending on what comes about here.

200gr 3.6gr Clays 230gr 4.0 Clays 200gr 4.0 Clays

739.90 828.10 790.1

687.55 793.30 810.9

766.20 815.00 804.2

712.10 839.60 671.1

665.60 829.00 787.1

716.60 821.10 799.4

703.60 824.90 799.2

719.00 831.50 812.3

741.20 830.30 803.5

749.90 814.03 817.9

AVERAGE 720.17 822.68 789.57

pwr factor 144033.00 189217.09 157914.00

I am looking for a recommendation on were to go from here?

O and these are all out of a Taurus PT1911 5"

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The extreme spread you're getting with the 200gr bullet is way too much...slightly over 100fps on one and 141fps on the other. That would have me concerned...one of those low rounds and you could fail to make major at a big match.

Are you sorting the headstamps on your cases? Did you check the crimp on those 200gr loads? If the crimp is too light and/or there isn't enough neck tension (more important) you can get pretty erratic velocity. I think that load development works best when you remove as many variables as possible and case variations can be pretty noticable. Then, once you've got a load that works well you can mess around with mixed headstamps and see how it does for consistency. If it isn't a factor then you'll know it for sure.

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I needed around 4.2 with their 200gr SWC to make major in my 5" Kimber. I agree that the ES on the 200 grain bullet data is too wide. Are you sure the powder charges were accurate for each load? Also, why is the 230 grain bullet data running faster than the 200 grain bullet with the same powder charge?? Am I reading something wrong on the cart?

Trodrig

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It was not really bright out but I was not using the diffusers, I did manage to shoot the left stakes several times though!!!

Mixed brass

WLP

aol. 1.245

crimp .469

I do pull about every 40-50th case to check powder and they all read the same as when I started.

Edited by cooter79
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What's the distance from the muzzle to the chrono? I usually put it at 10 feet to make sure the gases don't mess with the readings. I used about the same OAL and crimp when I loaded master blasters. You might weigh charges in 20 or 30 rounds and run them over the chrono. Also, do like Bart suggested and use all one brand of brass just as a controlled experiment.

Any signs of pressure in any of your loads? Flattened primers, etc?

Trodrig

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Hey Cooter,

When I am getting ready to Chrono, I'm like the posters above, I try to eliminate as many variables as possible. While you may not shoot a particular headstamp any other time, when you are going to chrono, try to do so. If you use Winchester primarily and have a few Amercs :sick: thrown in, your SD and ES are going to be large. Also, as stated above, make sure your crimp is consistent. I almost minored at A6 a couple of years ago because my crimp die had backed off. It happened again this year but I caught it before I went to Nationals. (I don't think it will come loose again :devil: )

Anyway, remove the variables and then work up your load.

YMMV but it worked for me

dj

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I needed around 4.2 with their 200gr SWC to make major in my 5" Kimber. I agree that the ES on the 200 grain bullet data is too wide. Are you sure the powder charges were accurate for each load? Also, why is the 230 grain bullet data running faster than the 200 grain bullet with the same powder charge?? Am I reading something wrong on the cart?

Trodrig

A 230 grain bullet with the same COL will use more case volume, thereby increasing pressure, hence velocity.

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OK I was shooting around 5ft due to my poor shooting abilities on Sunday and taking out the diffuser rods several times. I made up some more loads this morning using all winchester brass.

I am noticing that my press varience in clays is + or - .1 gr. Is this acceptable or should I be looking for rock solid consistancy.

I will run through the chrono tomorrow after work and show the results. I will also put it farther back and try shooting off the bench over the chrono to help in not hitting it or the diffuser rods.

I also agree that the 230gr shoots a little softer but I have 10k of 200gr and think I am going to like it once i get a good load figured out. I may try some w231 but I don't have enough laying around to make 20rds.

Edited by cooter79
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Guess the range i normally go to is now renting out for the next 4 Tuesdays to some agency for practice and I shoot matches on Thursday nights so I will have to wait until either Saturday or Sunday to get some chrono readings.

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  • 2 weeks later...

I suspect you will be right in there if you use about 4.2gr Clays. I'm planning to chrono exactly that load soon.

Here's my data for a similar load, at 4.3 gr Clays, chronoed at 10' from muzzle:

200gr PrecisionSWC

WinLgPrimer

1.250 OAL, 0.470 crimp

RP brass

AvgVel=848fps (170PF)

ES=48

StDev=12

WIN brass

AvgVel=837fps (167PF)

ES=28

StDev=10

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I suspect you will be right in there if you use about 4.2gr Clays. I'm planning to chrono exactly that load soon.

Here's my data for a similar load, at 4.3 gr Clays, chronoed at 10' from muzzle:

200gr PrecisionSWC

WinLgPrimer

1.250 OAL, 0.470 crimp

RP brass

AvgVel=848fps (170PF)

ES=48

StDev=12

WIN brass

AvgVel=837fps (167PF)

ES=28

StDev=10

I am shooting matches on Saturday and Possibly Sunday so it may be Tuesday before I get to the chronograph.

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If your still looking for info, you might try a different powder. I had to get to about 172-173 PF to start to get consistency with clays, it ended up being a pretty good load, I was using a berrys bullets 185 HBRN. I don't really want to say what the powder weight was, it was over max to make major but with the hollow base, and loading a hair long that what it took and not really any bad pressure signs. Anyway, until I got to about there the SD was huge like yours.

"get rid of the taurus"?

Why have you had a bad experience with one? have you ever shot one? Do you know anyone that has ever had/shot one? Just because something is inexpensive doesn't mean that it isn't just fine for what that person wants.

My $.02.

Jason

Edited by shooting for M
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