6.5 x 284 SD problems

[Varmint Hunter]

I'm working with a new 6.5x284. The rifle has a 29.5" Lilja, 8 twist, 3 groove barrel with a Vais brake.

I've been loading 142 SMK, 139 Scenar & 140 A-MAX bullets. Loaded mostly with H4831sc but have tried a few loads with RE22 and IMR 4350. Using Lapua prepped brass and Fed 210M primers.

With all bullets loaded .005" into the lands I'm getting SD's between 20 & 30. The accuracy is ho-hum with groups running between .75 - 1.5" @ 200 yards. In desperation, I loaded all three different bullets at .005" off the lands and most of the SD's dropped. A load of 51.5 H4831sc gave SD's of 40 with bullets into the lands but dropped to an SD of 5 when loaded off the rifling. Had a few other single digit SD's when bullets were loaded .005" off the rifling.

Normally, loading into the rifling doesn't cause SD to raise and frequently causes it to drop. Does this situation indicate something?

Anyone else using a Lilja 3 groove in the 6.5x284?

VH

 

[goodgrouper]

I have had two 3-groove barrels and I am sad to say that there is definetely some "voodoo" associated with them that I haven't been able to pin-point yet.

You already know this but,
the bottom line is you have to give the gun what it likes or it will frustrate you to death trying to force it to like what you like.

How are those long bullets shooting when off the lands?

 

[Varmint Hunter]

The rifle shoots slightly better when bullets are seated .005" into the rifling even though the SD is MUCH higher.

As of yet, I haven't figured out why this rifle refuses to shoot. Best single 3-shot group was .70 @ 200 yds. I've been talking to John Hoover who suggested that I get the SD down to 4 - 7 before I worry about anything else. Now I've got brass sorted into 5 piles and am putting bullets under the microscope. /ubbthreads/images/graemlins/smirk.gif I'm just a Varmint Hunter, never figured on going this far. The odd thing is that my 7STW Sendero (custom job) easily outshoots the 16.5lb 6.5x284 and it it gets single digit SD with Reminton factory brass which is prepped but not sorted. /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/crazy.gif /ubbthreads/images/graemlins/confused.gif

My H4350 has just arrived and I'll give that a try. I may also try loadiong bullets .020" into the lands to see what that does for the groups.

If all else fails - I'll moly coat - that cures everything; doesn't it? /ubbthreads/images/graemlins/grin.gif

VH

 

[jb1000br]

VH--GO IN THE LANDS MORE!! More lik 15-30 thou in -- 5thou is no good cause you will were that off during break in, then you will not be IN anymore.

i am using 51.6 4831SC and the 142 at about 15thou in -- kreiger for about 2900-2920

shot a few 3 shot groups like an "OAL ladder" start at the rifling and go in in 5thou increments till you are 30thou in

shoot them in 3-shot groups at 200yds+

i did this originally and do it periodically to monitor leade advancement. 3-shots will give you enough feedback.

what velocity and pressure you getting with 51.5?

report back /ubbthreads/images/graemlins/wink.gif

JB

 

[Varmint Hunter]

jb1000br,

[ QUOTE ]
what velocity and pressure you getting with 51.5?

[/ QUOTE ]

142 SMK loaded .005" off rifling with 51.5 H4831sc averaged 2,811 ft/sec (SD 8). 52.0gr raised velocity to 2,877 ft/sec.

Seems a bit slow for a 29.5" barrel but that's what I get on my Oehler 35P.

Pressure?? - Bolt lift and spent primers both good.

VH

 

[Guest]

I also found that my 6.5x284 likes the 142 SMK about .015" into the lands. Can't remember what the SD is for the load I shoot but it's 50grs of H4831SC out of a 27" Obermeyer 5R barrel and the velocity is around 2850. In last Saturday's 1000yd match I shot the smallest group of the LG match which was also a personal best, 3.625" for 5 shots.
Wayne

 

[jb1000br]

More powder cap'n...YOU NEED MORE POWDER!!

get her up to 2900-295 and put them in the lands, i bet the es comes to less than 30fps.

JB

 

[goodgrouper]

VH,

I load 140 vld Bergers with 50.0 grains of RL22 in a 30 1/2" barrel-8 twist. I seat the bullets about .010" into the riflings and I get 3115 avg and sd's of anywhere from 4 to 6 on a 10 shot string says my Oehler 35. For what it's worth.

 

[Fiftydriver]

Varmint Hunter,

Have you checked your neck tension consistancy? You said you are using prepped cases. Are these neck turned? This is generally not a problem witht he brass you are using but it can cause some velocity variation increases.

I generally like to use a bushing die for my extreme accuracy rigs. I used to een load them 0.050" long and use about 0.001" crush fit in the neck tension.

WHen the round was chambered it would seat itself to a consistant length from shot to shot.

This was for my extreme accuracy rigs. Now I just seat well into the lands as stated with about 0.002" neck tension and has worked great.

I have used several 3 groove Lilja barrels and have not had a problem. Most have been chambered for the 6.5-06 AI with bullets such as the 140 gr A-Max, 142 gr Sierra and Wildcat and the old 155 gr Sierras.

I have seen alot of guys get so hung up on extremely low spreads that they pass up some very quality loads. Shoot the loads at the ranges you will be using them and this will tell you more then groups at 100 and 200 yards.

Those long VLD bullets are just settling down at 200 yards. I would suspect you will be holding sub 1/2 moa groups at 500 yards, probably in the 1.5 to 2" range at 500 and even 1/2 moa out to 800 yards or so.

To be honest, with a VLD bullet, anything under 3/4" groups at 100 yards is worth testing at long range. You are getting this class of accuracy at 200 yards so back up and see what happens.

I also agree to put a bigger fire under those bullets. Often a harder thump in the rump will tighten not only your velocity spreads but also your groups.

Good Shooting!!

Kirby Allen(50)

 

[Varmint Hunter]

FiftyDriver,

Been away for a few days. The Lapua brass is neck turned for a finished (loaded) neck diameter of .287". The chamber has a .290" neck.

I have been using about .002" neck tension with a set of Redding Comp bushing dies.

Loads are a bit light as I am still working up. Time for more horsepower and more rifling engagement. I'll keep you posted.

VH

 

[jb1000br]

any news??

JB /ubbthreads/images/graemlins/confused.gif