Caribou Gear Tarp

Mag Speed or Chronograph?

Original load was 49grains but when a new 8lb keg was opened I had to drop it to 48.8 to get same results.
 
7F6A3D14-4340-46B9-9F7A-3816F5AD47D6.jpg

I received quite a few PMs asking why a chronograph for load development. I had been reading all of the info that Vikingsguy posted above in regards to accuracy nodes thru FPS deviations. I picked up a Caldwell from a member on here and did this testing today. From the target at 100 yards you can see if I was just using groups 2 and 7 show the best. By adding the Chrono data to it you can see that 6-8 has the least FPS and SD deviation. This narrows my next level of testing to a .6 grain spread.

This was my first try hand loading so open to ideas.
 
Oh I see you’re doing an OCW test at 100 yds. They work well also. Center of group for 6and 8 appear the same, I’d be curious as to what changed group 7. Three shots work good enough for this. Reshoot to see if it repeats. I’m assuming seating depth, primers, cases are same for all loads. A good start.
 
I reloaded 10 rounds of group 7 with 10 more rounds .1 grains on either side to see how consistent it will stay. All of the rounds were seated the same at 2.725 which is about a .075 jump.
 
Only problem that I had with the magneto speed chrono was it didnt like muzzleloader bullets with a sabot. now I dont have a chronograph.
 
With a +/-.1 gr accuracy as noted with this type of scale, isn’t it an exercise in futility changing loads only by .1 grain. I mean as the advertised accuracy states you could be trying to weigh in .1 increments but in fact the load could be .2 gr or .15 or .17 gr. Just my observation. I think your .2 gr increments will suffice for what you are trying to achieve. I believe you are working with a factory gun also.
 
.1 grain increments are a waste of time and components. Maybe some gain will be founder in smaller cartridges. Maybe. In larger cased cartridges, not so much. mtmuley
 
With a +/-.1 gr accuracy as noted with this type of scale, isn’t it an exercise in futility changing loads only by .1 grain. I mean as the advertised accuracy states you could be trying to weigh in .1 increments but in fact the load could be .2 gr or .15 or .17 gr. Just my observation. I think your .2 gr increments will suffice for what you are trying to achieve. I believe you are working with a factory gun also.

That makes sense, the rifle is a Legendary Arms Works Professional. It is a tight tolerance small production factory rifle.

I already loaded up the 10 #7 loads. Should I repeat #6 and #8 as well or just focus on #7?
 
Seem' to me that all scale's are guaranteed to +/- .1 accuracy. Even the digital ones.
 
I wanted to give an update on this. I shot the 10 loaded #7 rounds and ended with a extreme spread of 127 FPS. I shot it in two 5 round groups and the were about the same as #6 and #8. I didn’t like that spread as at distance that 127 FPS spread would really of opened up that group. I definitely see a benefit to shooting over the Chronograph. I would of wasted more time and components chasing that load if I was not able to know the speed spread.

Reading on other forums this is a common experience from RL16. So I cut my losses and ordered 3 lbs of H4350 to try the test over again.
 
An ES of 127? What was you ES from the previous groups? I’ve never seen one that great for the same charge weight
 
An ES of 127? What was you ES from the previous groups? I’ve never seen one that great for the same charge weight

I put them all into a spreadsheet, my math was a little off at 127. The group that was showing the most promise was at 78FPS over 15 rounds, as I played with seating depth they started getting significantly worse. I have no idea why it went to throwing 3 consistent low FPS rounds at 26xx FPS. They were all charged the same in that lot, there were no changes to my beam scale. I only loaded 5 and 3 of the 5 were low and the other 2 were 2846 and 2895 which is more normal. So I tossed that data and went back to the bench and loaded 5 more up with the exact same set up and the FPS shot up to an average of 2960. At that point I gave up on any more testing.
FPS.PNG
 
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