Help w/ 6.5x284 120g A'Max

[NealWright]

I'm new to just about all this, and am working with a Savage F'Class all stock. I can find next to NO information on this "lightweight" bullet out of 6.5x284.

I have Lapua Brass, Fed #210M primers, H4350, and 120g A'Maxs.

Bullets won't come close to touching lands, so I'm seating the bullets so that the base of the bullet is fully supported by the neck. Don't know any other way?

Couple strange results. We tried to run an imcremental ladder trial last night. Mixed results, nothing real conclusive ... but seemed to hover around 48.0g H4350. Weather was too crummy to get chrony to work right, and it was getting dark.

Loaded a few round this afternoon, was able to fire 8 rounds. Insane wind (30-45mph) gust, and really not worth beating myself trying to keep on paper.

Velocity was really strange. Chrony seemed to be working fine this time. 3035-3045fps. This was with 48.0g loads ... Hodgdon shows 49 as max, and ~2900fps. Anyhow, just looking for some general info trying this load? Any help? Thanks, Neal

 

[therifler]

your savage barrel is chambered with a very long throat .you will just be able to get to the rifling with 140 vld's. then you will have to hold by less than .100 tho. on body dia. . i would imagine the 120's are jumping a mile . 4350 H 48grs. is well below max on even the 140 with that chamber . that being said i have seen some of these rifles shoot very well even with that big jump . you should have absolutely no pressure but if you want to get to the rifling you will have to rechamber . i shoot 120 bergers out of my 6.5 x 250 they shoot great .amax did not work that well . T.R.
www.thrifler.com

 

[camac]

Here is some info I had in my logs from original savage barrel using the 120Gr sierra - no experience with the amax sorry. The 120 Sierra shot better than any of the 140gr (Berger, sierra, Lapua) for me but I ended up changing barrels as not high enough BC. Have tried the 123 gr Sierra since on another barrel and would be good to try with better BC though.
4350 took it up to 50 gr and 3160 fps but accuracy node was at 48.5gr and 3080fps. Liked an 80 thou jump. I could reach the lands with about 0.100 inch seated in neck in my chamber though.
4831SC 54 gr and 3120 fps max load and accuracy node.
As always work up slowly and check pressure - especially with savage as head space can be different every time you do up the barrel.

 

[NealWright]

Wow, that's really great information!

I'm a little less nervous about my velocity, seems right in line with what you have ... 48g, ~3040fps. I was afraid of erronious reading from my chrony again.

Surprised to see pressure signs at this charge though. 48.0g is just a slight primer crater ... we stopped at 48.9g which had slight-moderate primer craters.

Maybe I'm trying to seat too deep still? My OAL is 3.01". This is seating the bullet to fully support the major diameter of the bullet in the case neck. Case neck is ~.270", and I'm not talking about the boattail, but the body of the bullet.

You guys are seating bullets out to only ~.100" of the body supported? That would give me a lot of extra length, I just figured the bullet needed supported better?

By the way, my local matches are at 300yds ... so very short for this caliber, and better'd by the 6BR and PPC ... but this is what I have Fortunately, it also allows me to compete in the "factory" class.

Thanks again for any help! Neal

 

[camac]

Neal,
Cratering primers is pretty common even before max load is reached. Some guys bush the savage firing pins to minimise this. I use ejector marks and case head growth for indicators on my 6.5*284 with Lapua brass. Any case head growth and I back it down. Same with ejector marks.

Seating the bullets out this far is far from ideal and you must rely on contact with the lands for initial firing pressure, plus hard to keep em with low runout. Will be up to you to test where is most accurate for you though.

The 120gr is a great 300yard bullet. I found the 120 sierra much more accurate in my savage barrel and regularly put down 1 inch groups at 300 compared to best groups of 1.5 to 2.0 for the 140gr Bergers, 139 Lapuas and 142 MK.
The 120's were good enough to stay in the 10 ring if I did my part. The 140 class were giving me regular 9's even without wind.
3 interesting comparisons for my loads are 120 vs 123 vs 142 Sierra matchking (using my loads and JBM calcs)
at 300 yards the 120's at 3120 fps move 0.22moa for every 1 mph wind,
The 123'sat 3120 fps move 0.17moa for every 1mph wind
the 142's at 2920 fps move 0.16 moa for every 1 mph.

Therefore at 300 yards for my rifle and loads I would need to misjudge a wind gust by 20 mph for the 142's to make up for 0.2moa less accuracy than a 123 gr. The 120's only 4mph. In the real world I would judge better than 4mph on 8/10 shots so for 8/10 shots I would get as good or better score with the 120's and for 2/10 with the 142's. AT 300 ACCURACY RULES. Of course some rifles shoot the higher BC bullets very well anyway but I couldn't get em to work as well in my savage barrel. Worth trying a few bullets to get the most accurate though.

Trouble with 6.5 x 284 is you will burn the barrel out quickly trialling all this. I couldn't get to the lands in the savage after 400 odd rounds so replaced barrel - I have a reamer now though so will go back and rechamber it and try 123's in that barrel again at some stage.

At 600 the 123's are still very close to the 142's but 120's start to fall away. 1000 and its 142's all the way.

 

[k80skeet]

As far as being a barrel burner the 6.5 X 284 is a super long rang rifle if you can afford the time and trouble of changing barrels every 600 to 700 rounds. After replacing 4 barrels I am ready go to another caliber with a little more barrel life.

 

[camac]

I agree with you on that one - I am looking at options as well.