300 win mag loads

[dcopas78]

Hey all,

My dad has a Browning Hells Canyon long range in 300 win mag that we are trying to develop a load for. As of now, he is trying to get it worked up using his old standby, Barnes TTSX 180 grain. We are having a heck of a time getting what I would call a good group with it. The best we could do was about a 1.5 inch group at a hundred yards. Not horrible but we want at least sub MOA or better. We have went up and down with powder charge with little to no significant improvement.

With the Hornady OAL gauge it looks like there is a heck of a lot of free bore and the mag is sized to take a much longer cartridge, it seems. I've convinced him to try the 180 Berger elite hunter (much different bullet performance I know) and I've also ordered some 168 grain Nosler LR. Between us, we have 4different 30 caliber guns so plenty of places to use the bullets. I'm going to call Browning this week and talk to their techs to see if they have any suggestions. My big ask from your a is to see if you all have any load suggestions or experience with this particular firearm. Thanks in advance!

 

[mtmuley]

Accubonds. 180's first, 200's if those don't shoot. 181 Hammers if you must have a mono. mtmuley

 

[406LIFE]

I got both AB and Etips to pattern subMOA out of My Hell's Canyon Speed. I'll have to get the recipe for you.

 

[mtmuley]

I got both AB and Etips to pattern subMOA out of My Hell's Canyon Speed. I'll have to get the recipe for you.

Sharing load info is usually a bad idea. mtmuley

 

[VikingsGuy]

What powder? Did you do a ladder or a optimum charge weight test or lock for chrono flat spots? What are your SDs looking like? Have you tried to optimize jump to the lands? As you probably know, lots of variables to be considered, bullet is only one of them. And how many rounds since last good barrel cleaning?

 

[Idahoarcheryhunter]

178 grain eldx with a stout shot of h1000 did the trick for a friend, as always work up your own load carefully.

 

[MT_Chad]

Go down in weight on the copper bullets. The 165 ttsx was developed for the 300 win mag, mine shoots them quite well with h4831sc.

 

[dcopas78]

What powder? Did you do a ladder or a optimum charge weight test or lock for chrono flat spots? What are your SDs looking like? Have you tried to optimize jump to the lands? As you probably know, lots of variables to be considered, bullet is only one of them. And how many rounds since last good barrel cleaning?

So far we have used rl22, imr4831 and will probably pick up some rl19, ramshot magnum. We have loaded 3 rounds, usually varying weights at 0.5 grains between max and min loads recommended with both powders. All weighed out on an analytic scale so I know we don't vary by more than 0.020 either way on the weight per 3-rounds. Unfortunately, chrono took a nose dive today when dad accidentally knocked it off the tripod. Knocked a wire loose that I'm going to re-solder. Hope that fixes it. We haven't adjusted the COAL yet, and I think this is probably some of the inconsistency issues. A lot of work to do yet. Thanks for the input.

 

[VikingsGuy]

Go down in weight on the copper bullets. The 165 ttsx was developed for the 300 win mag, mine shoots them quite well with h4831sc.

A good point - when shooting monos best to go down a size.

 

[VikingsGuy]

So far we have used rl22, imr4350 and will probably pick up some rl19, ramshot magnum. We have loaded 3 rounds, usually varying weights at 0.5 grains between max and min loads recommended with both powders.

I would try magnum (as you noted) as it is marked as Barnes most precise in their load data for 300WM. I would also try H4831SC as the extreme powders are great as the weather changes.

 

[Coach Chris]

The 2018 is a 1-8 twist. I would be looking at heaver, high BC bullets like 212gr ELD-X, 210 VLD Hunting, 215gr & 230gr Berger Hybrid's, 210gr AccuBond LR

 

[Millsworks]

If the barrel twist is faster than a 1-10, like a 1-8 as mentioned above, the 180gr. may be the lightest weight that shoots decent.
It may prefer 200 grains and up, paired with a good slow powder like R26.

 

[HighDesertSage]

My Browning loves 165 ttsx's and h4831sc.

 

[dcopas78]

The 2018 is a 1-8 twist. I would be looking at heaver, high BC bullets like 212gr ELD-X, 210 VLD Hunting, 215gr & 230gr Berger Hybrid's, 210gr AccuBond LR

Dad has the previous model 1-10 twist. He got it earlier in the year on sale because the newer models were due to come in. I agree, if it had that faster twist, we wouldn't hesitate going heavy and seating as long as we could with the mag and lands tolerances. I ran the info through Berger's twist rate calculator and it recommended the 180 grain EH. At least with those, we can load them long to try to close the gap between ogive and lands if we need to. Thanks for your input.

 

[88man]

Mine likes 180grn Accubonds and R22

 

[noharleyyet]

Sample the 181 Hammers, you won't be disappointed. Excellent support.

 

[ND_Hooligan]

Have an older A-Bolt that is consistently shooting under 2 inch groups at 500 yards with 180 grain TTSX and 4831sc powder. Chrono's at 2910 fps.

 

[hntnnut]

I'm running 215 bergers pushed by H1000 with good resaults.


Richard

 

[GlockZ]

I shoot the 180gr TTSX, pushed by IMR4831, with fantastic results, also played with 168gr versions and get the same great results. my browning was a little finicky at first, but settled down and shoots moa or better.

 

[tom338]

if you are not changing your AOL with barnes bullets you are missing the mark by miles. Load 6 sets of 3 cartridges. Start .030 off the lands with the first 3 and then seat the next 3 .010 deeper, then the next deeper until you get them all loaded. One will shoot way better than the others, tweek that load. And start by using a good stiff load of the powder you want to use, towards the max load in the book, maybe 2 grains down. just adjust the seating depth, not the powder charge. Seating depth with barnes bullets is critical.