Jump to content

Barnes 130 grain TTSX


redding

Recommended Posts

Hi

Some thoughts from the gurus on here please.

I am trying to develop a recipe for a .308 using Barnes 130 grain TTSX

The attached picture shows results using 46.00, 46.50, & 47.00 grains of RS52

I have a 50 thou jump as recommended by Barnes

The barrel is a Lowther Walher hand lapped Match grade at 21& a 1/4" long

The cases are freshly annealed, sized with a redding bushing die and have a light crimp.

I can not work out whether to try seating deeper, I dont get why they all print left of bull when my regular load hits dead centre

I have also tried with a 10 thou jump and that prints to the same point.

Velocities are all around 2900 to 3000 fps.

Any comments welcomed

 

Barnes 130 ttsx .308.jpg

Link to comment
Share on other sites

Did you have any wind flags out when you were testing, might just be prevailing conditions on the day.  If not could just be down to different jump and barrel whip from using a different bullet and it's interaction with barrel harmonics, I don't think barrels just vibrate up and down.  

I generally test seating depths in 5 thou increments starting in the lands and moving out.  I don't know anyone who crimps bullets and if it was me I would try that first, shoot crimped and uncrimped side by side and see what happens.  

That 50 thou recommendation to me is just a complete guess, every barrel/bullet combination is different and what works for one will be completely wrong for another.  I suppose you could say it is a starting point but you have to test yourself with your own components in incremental series so can can see the difference each small change makes as you did with charge weight.

 

 

Link to comment
Share on other sites

I have used this bullet quite a lot and have found the jump to lands or 50 to 80 thou to work well. I think giving these bullet a jump to lands is about avoiding a pressure spike as much as anything.  Plugging the numbers in to Quickload it looks like you have some leeway to increase the powder charge a bit whilst watching for signs of pressure. I have found good results in two 308 win rifles at velocities around 3050fps (20 inch 1 in 10 twist) so it may be that you are just off a node. Half grain increments may also be a bit coarse to identify what is going on, Personally I use 0.2 to 0.3 grain increments. It sounds like you have some chronograph data, what were the SD and ES numbers like?

I have also seen lateral displacement between different bullets, that at least in my lighter profile stalking rifle is very consistent. I put it down to differing harmonics and dont lose much sleep over it. 

Link to comment
Share on other sites

8 hours ago, srvet said:

I have used this bullet quite a lot and have found the jump to lands or 50 to 80 thou to work well. I think giving these bullet a jump to lands is about avoiding a pressure spike as much as anything.  Plugging the numbers in to Quickload it looks like you have some leeway to increase the powder charge a bit whilst watching for signs of pressure. I have found good results in two 308 win rifles at velocities around 3050fps (20 inch 1 in 10 twist) so it may be that you are just off a node. Half grain increments may also be a bit coarse to identify what is going on, Personally I use 0.2 to 0.3 grain increments. It sounds like you have some chronograph data, what were the SD and ES numbers like?

I have also seen lateral displacement between different bullets, that at least in my lighter profile stalking rifle is very consistent. I put it down to differing harmonics and dont lose much sleep over it. 

Barnes does the.050 off the lands for pressure spike avoidance. As to why they print left imo its nothing more than this projectile just does.... yes simplistic i wish i had a better explanation. Most of my rifles print to center with any projectile weight regardless.........not all.

Baffles me too. Best wishes for good shooting

Link to comment
Share on other sites

Thanks all for taking the time to reply

There was no wind as I test in a narrow gulley in a wood.

The ES was 19fps

My regular 155 grn ELD,m groups at .40"

Barrel twist is 1-10" by the way

I will go up to a 75thou jump, if thats no good I will give up on the Barnes, I have almost used a box full already, at £50.00 its no joke!

Link to comment
Share on other sites

Hi. 

I have been using Barnes bullets for a lot if years now in my 308.

They have all been loading to be 20 thou away from the rifling and never had any problems.

I use TTSX 150 grain. with 42.5 grains  of VT140

I changed to Hornady sst bullets but I had a few beasts run about 30 yards. This does not happen with the Barnes so quickly reverted back .

Using the Barnes bullets they practically drop on the spot , at the most maybe go a few yards .

It is worth persevering with the Barnes bullets.

Cheers

Shoppe 

Link to comment
Share on other sites

1 hour ago, shoppe said:

I have been using Barnes bullets for a lot if years now in my 308.

I use TTSX 150 grain. with 42.5 grains  of VT140

Using the Barnes bullets they practically drop on the spot , at the most maybe go a few yards .

Have you recovered any bullets from carcasses in that time, and if so, what did expansion look like?

What barrel length is your 308, and do you have any idea what velocity you are chucking them at? 

Link to comment
Share on other sites

1 hour ago, shoppe said:

Hi. 

I have been using Barnes bullets for a lot if years now in my 308.

They have all been loading to be 20 thou away from the rifling and never had any problems.

I use TTSX 150 grain. with 42.5 grains  of VT140

I changed to Hornady sst bullets but I had a few beasts run about 30 yards. This does not happen with the Barnes so quickly reverted back .

Using the Barnes bullets they practically drop on the spot , at the most maybe go a few yards .

It is worth persevering with the Barnes bullets.

Cheers

Shoppe 

That has been my experience with them as well. Very few roe deer take a step after being hit. I have never recovered a bullet yet. Mine are from a 20 inch barrel with 46g H4895 at 3000 FPS. My sons rifle worked well at 3050fps, also from a 20 inch tube

Link to comment
Share on other sites

Hi. The rifle is a tikka continental with a 600mm barrel.

I have never put a chrono to this rifle but I will soon. I am expecting  it to be about 2670 fps.

I did recover one bullet from a hind once. It had stopped just under the skin at the "exit "side of the beast. It could be seen like  small lump before I cut it out.

It had mushroomed very good . I did not weight it but it seemed to be pretty much  still there.

To me they are far better than "conventional" bullets.

The targets just seem to drop on the spot.

I have been stalking with a few game keepers and the beasts go down so quickly, one commented that I had missed and the hind must have slipped and fell over! But this was not the case.

I could clearly hear the smack of the hit. He said he had never seen a beast just "topple " over like that.

Yes, the bullets are not cheap but I hate it when a beast runs off and I have to go searching. ( hornady sst )

Cheers

Shoppe

 

 

 

 

 

Link to comment
Share on other sites

It looks like you have a nice stable powder load from the three groups, with very little movement of the groups vertically.
I would try your 46.0g load with a .040", .060", .070" and .080" stand off. If you can see an improvement, then you could start to move in to it with 003" steps.

Forget the grouping to the left. the POI will move around as you change the charge and the stand off. The right hand chart is for vertical movement, but you can see the horizontal movement just above the light blue boximage.thumb.png.8a017d968fd3184da051b16e339d679c.png

I've just been through the process with Fox 150g in .308

Link to comment
Share on other sites

  • 2 months later...

Hi all

Got a mental block here.

The round on the right is a modified case used for measuring the distance to the lands.

The round on the left is my loaded round ready to go.

Query: the right hand round measures CBTO 2.290, the left hand live round measures 2.177.

The difference in CBTO measurement is -113 thou.

In the picture its plain to see that the visible difference in the CBTO measurement is far greater than 113 thou.

I am being a thicko here, what am I missing?

TTSX.jpg

Link to comment
Share on other sites

11 minutes ago, lapua said:

Looks about 2.9mm to me? Whats the problem?

i’d just keep increasing powder until group tightens or crack on with killing deer. Looks plenty good enough

The problem is that the live round CBTO measurement is visibly more than -113 thou shorter than the dummy round which is the CBTO for this bullet in my chamber, my loaded rounds are perfectly zeroed, I dont need to alter anything.

 

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Privacy Policy