155 Grain Scenars and 300 WSM

[Glock4ever]

Hello all,

I have been looking at the ballistics of the 155 grain Lapua Scenar bullet from a .308 Win and was wondering if anyone has tried driving the same bullet from a 300 WSM or a 300 Win Mag. I was wondering if the extra velocity would seriously improve the ballistics of this particular bullet. I have farted around with what the drop and what not would be with this bullet in a ballistic calculator but I would like to know if anyone has any real world experience firing these down range. I was wondering simply because the BC was so darn high but I have noticed that on Sierra's webpage they will list different ballistic coefficients for the same bullet with varying velocities. (they tend to be better as the velocity increases) I was wondering if it is the same thing with the Scenar.

I was thinking of building a .300 WSM specifically to shoot this bullet (appropriate twist, etc.) but I was wondering if ballistically it is even worthwhile to stay with this weight or just simply go heavier. I have to say I am kind of intrigued of the idea of driving the 155 grain Scenar to 3200-3300 FPS and seeing what it would do...

 

[Jeremy1]

If your going to be shooting the wsm I would recomend going to a larger bullet such as the 190 VLD berger or thr 190 Sierra.The velocity boundries for this bullet are about .500 at 3000 fps and don't get much higher.The wsm case was designed for heavier bullets.

 

[Glock4ever]

Jeremy I am not tracking what you are saying? Many of the other calibers have lighter weight bullets that travel at higher velocities. Unfortunately the these lighter bullets shed speed quickly and don't do as well at further distances. What makes the .300 WSM case any different from say a .243 Win or .30-06 for driving a lighter weight bullet faster? If you are saying the velocity boundaries for the Scenar are at 3000 FPS can you direct me to the literature for this? I am curious as to what happens to the bullet - fragment in flight? base of the bullet can't handle pressure? What are the problems associated with pushing the scenar faster?

 

[NormB]

154 Lapua/N550 and WSM

Hello all,

I have been looking at the ballistics of the 155 grain Lapua Scenar bullet from a .308 Win and was wondering if anyone has tried driving the same bullet from a 300 WSM or a 300 Win Mag. I was wondering if the extra velocity would seriously improve the ballistics of this particular bullet. I have farted around with what the drop and what not would be with this bullet in a ballistic calculator but I would like to know if anyone has any real world experience firing these down range. I was wondering simply because the BC was so darn high but I have noticed that on Sierra's webpage they will list different ballistic coefficients for the same bullet with varying velocities. (they tend to be better as the velocity increases) I was wondering if it is the same thing with the Scenar.

I was thinking of building a .300 WSM specifically to shoot this bullet (appropriate twist, etc.) but I was wondering if ballistically it is even worthwhile to stay with this weight or just simply go heavier. I have to say I am kind of intrigued of the idea of driving the 155 grain Scenar to 3200-3300 FPS and seeing what it would do...

I shot some 154 gr Lapuas in a 1-12 twist N550 powder..300WSM...31" barrel. 3450 FPS I shot some 135gr BR bullets at 3650. They got to 600yds real quick. Had a spotter watch the arc with the 154's at 1000yds... lots flatter than a 6Br. He was still talking about it at lunch after the match.

Its nice to have the extra 450 FPS at the muzzle... its still about 300 fps extra at 1000 yds . Transonic effects start around 1400 fps and you want to be well above that.

Looking at the BC charts... Velocity trades off against BC.. go light and fast or heavy and slow... the wind drift usually comes out awash.


The 1-12 twist will handle up to 190's. Lots of room to play with bullet weights

NormB

 

[Glock4ever]

Thanks Norm what kind of accuracy were you getting in a 1-12 twist? How much flatter was it at 1000m? Were you seeing a lot of drift? I know what paper says but I always find that the paper and real world ballistics can be noticeably different.

 

[NormB]

Thanks Norm what kind of accuracy were you getting in a 1-12 twist? How much flatter was it at 1000m? Were you seeing a lot of drift? I know what paper says but I always find that the paper and real world ballistics can be noticeably different.

Glock,

I have to rely on BC tables/programs for numbers here but they compare to my experience. 9 mins less elevation required than a 107gr 6BR at 3000 fps and 2 mins less drift. Its also 300fps faster than a 6BR at 1000 yds.

It was quite accurate, but my favorite bullet was a BIB187FB, BC of .525 for accuracy. I now use this for 1000yds.

1-14 twist would be very good for 154's but marginal for heavies. I shot some 175 sierras in a 1-14 .308 ...very accurate close range but wandered vertically at 1000 yds. Ordered a 1-12 twist 32" and made a .30/284 and thought the problem would be solved with faster twist and MV... still wandered up and down at 1000 yds. I don't shoot that bullet anymore. I rechambered the barrel to .30WSM.. lost an inch from 32 to 31. Planned to shoot 187BiBs at worlds but had shoot 154's at 700 and 800M. Couldn't get enuf 187s and had to ration the 187's ...I shot the 154's closer in.

Note... This is important.... Don't go to a world championship with a rechambered barrel and rationing your bullets.

At the world FC champs only 13, 6.5/284s beat it out of a couple hundred shooters. It held its own in the coached team match with 6.5/284's. That's where one of the guys compared its trace to a 6BR shooting for our team on the next target... a lot flatter. We had 2 shooters on the mound at 1 time.

Another note.. In F-Class Its hard to beat a 6.5/284. I've tried with .30/284, 6BR, 300WSM and now with 7mm/270WSM. The BC tables and on the range experience prove it. You can, but its tricky.

NormB

 

[Glock4ever]

Hi Norm,

Thanks for all the information. I am not looking to shoot the 300 WSM competitively (like I am a competitive shooter...) I am just interested in seeing a really flat 30 cal that will get out to 1000m. I mean tactically Snipers shoot 168 grain bullets out of a .308 WIN 600m is supposedly the top end of the effective range spectrum. If the 155 Scenar extends that to a 1 km wouldn't it do more for a WSM? BTW what bullet is the BIB187FB? I have never heard of it as I am only really familiar with the bigname bullets... I assume it is a 187 grain Flatbase?

 

[NormB]

Hi Norm,

BTW what bullet is the BIB187FB? I have never heard of it as I am only really familiar with the bigname bullets... I assume it is a 187 grain Flatbase?

You are correct. Its a custom benchrest bullet BIB stands for ballistic idiot bullets... Randy Robinett in Iowa.

Norm