6 x 47 Lapua velocity with N160

[londonhunter]

Can somebody advice

I have just finish load development with my 6 x 47 Lapua with the following spec

105 VLD Bergers hunt in a 26 inch lilja with 1 in 8 twist built on a BAT MV

loaded 5 thousand backed from the lands and 37.2 grains of N160

Muzzle velocity is 2910 fps and repeatedly i can get under 0.25 inch 5 shots groups

typical 05 shot velocity string ranges from 2890 to 2915 fps

Now a few friends are saying I am running them too slow and should start pushing

Its really a varmint rifle and max range is 600 yards

If I can hit a 6 inch gong every time or better I am very pleased

Should I carrying on load development and pushes into the 3050 fps speed range or stop here

Obviously I am not that experience so please can somebody guide me along ?

I am very aware of barrel life so to me further load development is pointless if I am

getting tight groups and can repeat them on different days as well

I guess what they are saying there is a high node around 3050 fps and there is less drop at that speed if I want to shoot further is that right ?

thanks

BTW there was a strange velocity it actually dropped when I pushed it to 39 grains in a few shots Why does one explain this

 

[alinwa]

I see nothing to change.

Yes, that's a little slower than some run but as long as your velocity spread (Extreme Spread, ES) is as low as your records indicate then I can see no real gain in changing your load. If you're not weighing your charges accurately on a good scale you may experience a gain if you do so.

Don't let anyone convince you that velocity and drop are important. CONSISTENCY is important, drop is not.

I cannot explain why your drop in velocity when going to 39gr. I would retest?

al

 

[John Kielly]

If you are tossing your loads....

I weigh all my charges, but meter close to the load I want out of a powder measure. I test my (electronic) scales with test weighs I have made that exactly equate to the load I want, leading up to saying that I'm real comfortable that my scales are reading true any particular time.

Now, when I toss that load out of the measure, I'll get up to half a grain variation in the average it throws depending on the weather conditions.

Maybe you ran into that issue.

By the way, I load N 550 quite a bit & have found that when the load is getting to the oh dear stage, the velocity increase tends to back off to almost nothing - but I've never sean it regress to less than what it was.

 

[Charles E]

. . . By the way, I load N 550 quite a bit & have found that when the load is getting to the "oh dear" stage, the velocity increase tends to back off to almost nothing . . .

That's fairly normal for a lot of powders. If you keep tilting the can to the "throw the cases away after a match" stage, velocity will usually pick up quite a bit.

I've never seen velocity drop when adding more powder either.