Budget chrono with a difference...

[marksman]

Marksman...ive never understood the "flat spot" theory...makes no sense to me...
I think i saw it explained how i understand it to not be useful somewhere in one of the links you once posted...

If you fire a string of shots at steadily increasing charges & look for a flat spot, you will find one, or 2, or 3......but who is to say that is an actual flat spot, & not the extreme ends of say a velocity scatter node...??...(not sure if thats a term, but hopefully you know what i mean)...

Ive tried it once before & chased my tail pointlessly...wasted a heap of time & money chasing a load where there wasnt one, well i dont think there was one, lost all confidence in what i was doing, so just went back to what printed at 100 & shot things...

usually Stix when l have done the OCW testing the results mirror the satterlee as in finding a flat spot in velocity shown by usually low es
so now l do the satterlee test beforehand with a target then based on that l do the OCW and know l am going to get the velocities
l have always said you dont need a chronograph to get a sweet spot load but it helps with the way l am doing it now,
gets you where you want to be testing quicker

l still cannot remember who on this forum it was that asked about the satterlee testing that pricked my interest

[TassieTiger]

I noted a flat spot when recently testing the 300...
I had decent accuracy from 66gns and 68gns and then 69.5gns test loads.
Using this chrono, I noticed that 68.4gns and 68.6gns - didn’t increase any speed from 68.0...had me scratching my head and wondering if I had not screwed up - so I replicated the same and got same results. For some really weird reason, some loads of 68.4 produce equal or even slower than 68.0.

I’ve tested this up to 72.0gns but there is a node at 66 and 68 and it’s just about right on 2850 and 3k respectively. I am getting inconsistencies up to 69.5gns. But 69.5 at this stage (no seating depth play) is not quite as accurate as 68. Over 69.5 and I seem to get a drop off in speed again and then flyers start coming in. More development to be done...

[marksman]

Good point marksman, i didn't think about thin barrels, probably could case more issues.

When it moves what effect does it have on the speeds

l dont really know if the strap sliding had any effect on speeds but the bayonet would droop so l dont think it would be working as it should
the manufacturers made the better strap catch set up pretty quickly because of the complaints

[Bill]

If the bayonet was drooping then you had buckleys of getting an accurate reading.

Took my magneto to the range yesterday and 30 rounds thru the heavy recoiling. 6.5 grendel it didn't shift 1 bit. 0.6moa 5 shot groups was as good as the gun has ever fired to, am yet to see any accuracy affect.

[Stix]

Bill...i get that if its not happening for you its not happening...
But im not shooting your 6.5...

And i dont get a shift in poi or change in group size with my heavy barrel 22-250 either...

Thing is, there is not much steel around the 7mm hole in my sporter barreled 7-08....so its understandable it probably whips around a little...

[Sergeant Hartman]

Hey stix is yours a sporter or the v3 one? Got a friend interested if you want yo let go for cheap, seeing it doesn't work that well

[Stix]

If i sound a bit abrupt above--i didnt mean to be..

.It works Ziad...and what do you call "cheap"...

And i must say, i think your attempt to subliminally convince me it doesnt work so your friend can get it cheap is pretty funny...

Yes its the V3...

But...doubt ill off-load it, because i cant afford any different options...
I just have to use it within its capabilities...but that doesn't stop me having a bitchy whine about it...

[Sergeant Hartman]

I am happy to swap my sporter for your v3 with a couple of cans of XXXX Gold your way.

Or just use a thicker rubber riser and increase your sensitivity as it might be a couple mm away from the barrel