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Hey Rusl, great you have access to a decent range. 2500fps would be commensurate with 41gr of 2209 I would think.
I would do as shooternz recommends and start at known data book COAL and work it up.
Measuring chamber length by closing a inert case in will give a few thou jammed in the lands reading and also I found I needed to repeat the measurement several times to get a 'true read'
I think I was at 45.5gr 2209 with 143eld. Running 120gr now.
Set a case up how I described and compare it to one of yours start with the simple stuff first also have you worked up to your load or is it the first one you've tried
Yea i worked up to this load, I have measured coal again and was bang on I'm just loading up some new rounds now with the seating depth quarter turn in from lands like north dude suggested which is about .3mm shorter than before, should put me .35mm off lands.
Thanks hopefully if the weather holds I will get some testing done one day this week and will post results.
One full turn on standard 14 TPI dies will give you ~1.8mm change, so 1/4 will be ~0.45mm. For your situation I would start at 0.5mm (20 thou) off jam so 1/4 turn is as near as damn it is to swearing.
Hi Rusl, in the interests of eliminating some obvious possibilities you haven't mentioned to what extent the cases are being sized prior to reloading; can we assume that the cases don't start out tight to chamber, and also that the case length is within the maximum spec so there is no chance of excessively long necks jamming the bullets when chambered ? There is also the possibility of embedded carbon build up in the throat & neck area resulting in much the same effect - worth checking for.
Also mate don't bother with the chrony, just get zero spot on and head out to 3-400 odd and shoot a group without dialling or holding over (be sure to have a target set up to take 12-24 ish inches of drop so a tall target). Measure the drop in inches or mm if you are a MIL guy and feed speeds into an app until the drop matches. Far more accurate than the lower end chronys.
Heaps of good info coming in here thanks, I'm pretty sure the chamber is clean as I did wonder if it might be somthing like oil or solvent in there so gave it a good clean out initially.
Brass is fired only in this gun and neck sized and trimmed with a lee trimmer with mandril that sets the length, also I randomly measure cases as I do it. Loaded rounds slide in with ease no stiff bolt closing etc.
Thanks gibo about the tip for working out velocity, that's how I did it to get the numbers I have, I used a left over sheet of gib board from a building site nice and big, but I was starting to think I may have been on the wrong track and a crony was the ticket. But I would way rather spend the $ on practice bullets, I hope once I have a nice load setup I shouldnt need to alter it again therefore the cronograph would sit with all the other stuff I have bought over the years and never use.
Measured bullet drop at a 'known' range dont lie mate :DQuote:
Originally Posted by rusl
also are you using an accurate g7 bc ie litz ?
some manufacturer bcs can be optimistic
As you have some Hornady brass, try it. I don't see the powder charge or CoL being the issue here.
I can load a couple of pills up that are very safe [emoji41] in Lapua brass And you can do a ladder test. Where in NZ are ya or are you in Nicaragua?
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Up in northland not quite Nicaragua mate, I have loaded a handfull up with a shorter coal and will try this first, I was trying to save the hornady brass for a eld-m load once I get a bit better and start shooting further. I was going off the hornady bc I will investigate this aspect further. cheers
Something else you can try, measure the grains of water from a case fired (but not resized) from your rifle. You have to have it full to the top of the case, tap it to raise any air bubbles and square across the mouth, doing it 2 or 3 times ans averaging the result is best. Send me the result and I'll feed it into Quickload, sometimes that will tell a story (and sometimes not).
Cheers
one other thing no one has asked yet.....are you 100% positive its 400 yards and not 410 or 390?????
I mentioned 'known range' in post 23 :DQuote:
Originally Posted by Micky Duck