Losts of questions, One at a time.

[Beelzebub]

Been reloading 40+ years. Probably not as good at it as I think I am or wish I was.

BUT....I can get several of my old factory barrel guns to shoot at or better than 0.250" with regularity..

So I've been working on some load data for my 243 Winchester, 700 VLS with 9.125:1 twist. About a month ago I bought several hundred Berger 95 gr Match Hunting VLD. Load I settled for came in well under 1/2". But I've never been one to leave well enough alone. I finally found a shop within 75 miles that carried something other than 3031, 4060 or 4831. I bought RL19, 7828SSC and H100V to experiment with.

To level the playing field and give myself something to do last Wednesday night while Noah was trying to find a place to drop anchor, I used a brand new RCBS neck sizing die and neck sized about 50 RP cases and then trimmed to 2.035". Chamfered in and out and cleaned primer pocket.

Seated primers with a hand primer and put them in the loading tray. Meticulously I slowly loaded every case using my scale. Each "load" was as close to the previous as I could possible get it. I loaded 5 rounds of 9 different loads. Three powders and 3 different charges of each. Each bullet was seated with the same RCBS seating die locked down tight. Here was my first notice of things getting out of whack. I started out doing my best to set the seater die at 2.710. Of the 45 rounds I loaded, none came up shorter than 2.710, but many came it around 2.715-718 I refused to long seat every bullet and then turn and twist the seater and mic every round 4 or 5 times.

How cold is a cold barrel? It was less than 50 this morning while I was shooting. Probably spent an hour shooting 45 rounds. How cool, warm or hot is normal for working up loads? I've read of guys pouring water over the barrel/gun. Putting cold rags on them................ I will say that on a couple of occasions the barrel was too warm for me to grasp with my hand and keep it closed.

I chronographed every shot using a $100 chrony set at abut 12'. Gun and Chrony were both in shade, so I felt comfortable the readings would be fairly accurate. At least I didn't get any error readings today.

What is an acceptable for extreme spread?

Here's what I loaded:

IMR 7828ssc 45.0 5 shot avg: 2783 ext spd: 41 3 sht grp .672"
45.5 2856 56 .632
46.0 2892 50 .496

RL 42.5 2753 45 .495
43.5 2868 56 .538
44.5 2901 44 .235

H100V 41.0 2920 19 .692
42.0 3026 48 .508
43.0 3091 64 .583

Oddly, the load with the most consistent velocity was the biggest group. I sure had high hopes for the new H100V or 7828ssc I like RL19 a lot though

If it takes getting my feelings hurt to learn something about tightening up these groups then I gladly welcome the criticism.

thanks to any and all....
Beelzebub

 

[Beelzebub]

Sorry for all of the typos. I tried to clean it up and format the numerical data. but when I saved the edit it came back in a mess and now I can't edit it again. the "RL" powder was RL-19.

 

[MudRunner2005]

That's impressive that 7828 SSC is getting those kinds of velocities in the .243 Win case. I would have figured it to be too slow for that small of a case capacity. Interesting results though.

 

[Beelzebub]

That's impressive that 7828 SSC is getting those kinds of velocities in the .243 Win case. I would have figured it to be too slow for that small of a case capacity. Interesting results though.

XXXXXXXXXXXXX

Using the same el-cheapo chronograph, I get 3080 fps using 45.5 of IMR7828 and a Hornady 105 BTPH Match. I was sure expecting more velocity than that. Especially from the H100V

 

[Predator 22]

If the barrel is to hot to touch you probably need to slow down. I let my barrels cool off completely between 3 or 5 shot groups.

 

[Dgd6mm]

What is your altitude? What is the length of your barrel?

 

[Capt RB]

Did you clean before changing powders?? I've had very good speed with 100v. I'm getting quite a bit more at 43gn with the 95 classic. But it is as far as I will go in a straight 243 because it will get hot in warm weather. Okay for the winter hunting I do.

 

[RT2506]

When you measure your COAL you need to be using a comparator to measure off the ogive of the bullet. The measurement from base of case to ogive of the bullet will be precise. Bullet noses have slightly different lengths and that was the cause of your different COAL when actually they were probably the same because the seater stem was seating off the ogive of the bullet. When you adjusted your seating stem to get what your thought was the same COAL you actually had different seating depths and that will screw up your groups.

Yep, slow down your shooting if the barrel is too hot to hold on to.

One other thing that I have found that helps increase accuracy is to deburr the flash hole on the inside of the case. Everybody except Lapua punches their flash holes and leave burrs sticking up inside which will cause the spark of the primer to be directed in an dispersed inconsistent ignition. Taking out the burrs let the powder be lit the same every time.

 

[Dgd6mm]

I had a Pro Chrono that liked the sun, I don't know if the Chrony is the same. For only five shots each the extreme spread does seem to be alot, I'm not happy when I see those kind of numbers with 10 shot strings. Let your barrel cool some and take more time shooting for groups. I do think your speed is a little slow.

 

[Beelzebub]

Many thanks to all who have replied.

Barrel length is 26".

Altitude is about 150 feet.

Didn't clean barrel between different powders. Cleaned it good before the testing and fired 3 fouling shots the day before testing.

I ordered a flash hole cleaner this morning from Midway. That and an RCBS competition seater die. Once I got the seater die set to 2.710 on a dummy round I tightened everything down and seated one more dummy to make sure I was still good at 2.710. That round was 2.712, so I let it ride. All 45 test loads were seated with that die without any changes.

None of the loads showed any signs of pressure or being stressed. As soon as my flash hole cleaner and new seater die comes in I'm going to bump up the powders a little and seat the bullets out to about 2,.820-825 and see what I get. At about 2.825" I start having trouble loading them into my magazine well. But I can drop one in the barrel and load two in the mag without too much trouble. If I can't kill what I'm shooting at in three shots I need to move closer or practice more.

Thanks again for all the responses. I will definitely slow down and let the barrel cool more.

B