243 80gr nosler ballistic tip

[foxpig]

Rifle.. sako A7 243 win

Bullet. . Nosler 80gr ballistic tip

Powder.. viht N140

Charge .. 41grains

Primer..federal gold match

Velocity.. estimated 3150 fps at muzzle

Cases.. federal fire formed

Oal.. 2.700.

Average group under half inch at 120m

 

Notes.. penetrates better than the vmax and makes a real mess of foxes over 150 yard . Any closer and the expansion is moderate.

[mutley]

are you sure on the balistics the norma 75grain vmax loads i use of factory ammo produce 3330fps according to the box and have a real time drop of 6'' @ 300 yards, if so i think im going to have get some reoads on the go.

[foxpig]

are you sure on the balistics the norma 75grain vmax loads i use of factory ammo produce 3330fps according to the box and have a real time drop of 6'' @ 300 yards, if so i think im going to have get some reoads on the go.

not 100% no, every book you read says max load is around 37gr for 3200 but my book says 41gr and im not having any signs of over pressure. so im guessing as i have a shorter barrel mine is less. ive tested this round on a flat feild( used an airplane landing strip) and this is the drop ive recorded..

[foxpig]

went up this morning with the measuring wheel and the 300 yard target was actualy at 280yards exact , not that that makes much difference but thats what there dropping at that range.

[gbal]

I would not rely on a short barrel to reduce pressures!!It will of course reduce mv by maybe 20 fps per inch.Most 80/85 grain bullets would be Mv about 3350,and with an inch and a quarter

high at 100,would be about 6 inches low at 300.(BCs around .26 to .32 in 85gSGK )

 

1/2 high at 100 and 3 low at 280 just does not fit with the above.Care and chrono,I think

 

Gbal

[sonic]

foxpig I read somewhere about N140 and some books max being higher than others seemed the advice was to use the data current for the date on your powder.

min max

 

5,2 80 FMJ Hornady 67,0 2.638N140 2,34 36.1 882 2894 2,68 41.3 978 3209

from 2008 vv manual

edition 9 says

2 80 FMJ Hornady 67,0 2.638 N140 2,04 31.5 831 2726 2,41 37.2 949 3114

which one?

there was also a reported trend of lower max on other powders and speculation as to whether it was better performance or lawyers the reason.

[foxpig]

In my book it says max load 41.3gr so im under that. Surely if im getting over 8 fireings out of a case then all is fine. My book is the vihtavouri loading manual.

 

Had the powder changed or something. How can 37gr produce the same mv as 41 gr.

Think I need to chrono and find out.

[sonic]

I know where you're coming from I thought the same. I can't help with newer powder mine was older powder I got a box full of Lee gear fired cases N140 and a few other powders I then got a 3/4 bottle from a mate which was 2008. Didn't have my chrono till the second tub.

I was using 40.5 with naked 58 vmax then 41.5 when I changed to moly max in 6th edition is 43.2. can't find my notes from chrony but it wasn't a hot load.just looked at 9th ed its same max.

Could it be the bullet design has changed?