Unable to develop load for rifle

[35WhelenAI]

My 300 WM pretty much settled on IMR7828. Really does well with the heavier bullets and a bit less charge weight than H1000. My personal preference is for a fairly full case but not compression. Mid to high 90% range works great.

Had the bolt stop shortened, took out the sheet metal filler in the magazine box and got a magnum length follower for my M70 Synthetic Matte Sporter. I seated the older Barnes 180 XBT out to 3.600 in and was able to get a bit more velocity with the subsequently slightly higher charge weight I worked up to. I tried fire lapping back in the mid-90s based on a Shooting Times article and I think I was a bit overzealous and the throat on that rifle is very long, lol.

Edit: Lee factory crimp die will get you consistent bullet release tension, helps eliminate potential inconsistent tension as case are sized and resized.

What ranges are you wanting to shoot at big game? Midway has 180 Barnes TTSX available, superb game bullet. Barnes doesn't have 180 TTSX data for H1000, start with mid range 200 gr Barnes data (which they have for H1000), watching for pressure indicators and you should easily get 3,000 fps.

 

[IDspud]

I might sell my whole set up. The though of dumping more money into a setup thats shooting no better than my short barreled gas gun makes me want to throw up. Over $5k worth of rifle/scope that just isn't working out. Not counting the stupid amount of wasted range trips and components.


I switched powders. Had one load shoot under an inch. Went back with more and once again opened up. Threw on my chrono and had an ES of nearly 70 and SD of almost 40.

Switched bullets to some Hornady ELDXs. More or less the same story. What the #$%& is this? One second a load is good the next it sucks. I'm not having this problem with my other rifles. This load for my Tikka was easy...

 

[35WhelenAI]

Gosh, sorry for the frustration. Seems to be nowhere else to look but the loading components. Not necessarily the bullets, brass or powder but how about the dies? You mention a mandrel to set neck tension. Have you tried running them up in a regular sizing die and letting the expander ball set neck tension and seeing how they shoot? Or doing the mandrel or regular resizing die and putting a Lee factory crimp on it? For the money you have in that set up, the cost of trying those things is minuscule and it may hit the mark.

 

[IDspud]

Gosh, sorry for the frustration. Seems to be nowhere else to look but the loading components. Not necessarily the bullets, brass or powder but how about the dies? You mention a mandrel to set neck tension. Have you tried running them up in a regular sizing die and letting the expander ball set neck tension and seeing how they shoot? Or doing the mandrel or regular resizing die and putting a Lee factory crimp on it? For the money you have in that set up, the cost of trying those things is minuscule and it may hit the mark.

I didn't start off with the mandrel. It was a somewhat recent addition to try and help fix any possible neck tension issue. It didn't help either.

 

[swavescatter]

Following. Just getting into reloading and have a Bergara B14 300 WM.

I've tried a couple 200+ grain cartridges (ELDX and Terminal Ascent) and it just won't shoot them. Another user here posted the same issue. Tight groups with lighter bullets. I think these rifles just might not like heavier bullets. Bergara provides the ammo they used to guarantee MOA and one bullet was the 185 Juggernaut.

I bought some 178 ELDX to try for my first foray...

Just bumping this up. Have you tried a 180gr or below bullet?

Which factory cartridge shot sub-MOA for you?

I have roughly the same rifle as you and I'm wondering if I should even bother trying to get it to shoot the 200gr+ bullets. I would think Bergara designed their 300PRC to shoot the heavier bullets, but perhaps they just don't work with the 300WM...

 

[S-3 ranch]

I had a model 70 .300wm that frustrated me to no end , trying to work up a load wit 200gr , never could figure it out, it would like 165gr nosler kinda, finally one day for peace of mind I grabbed some federal classic 180 factory and they got a .65 moa and I bought a case of the same lot # ammo
and called it a day , will power just couldnt make it do 200+ gr
I hear those bargara are very touchy in some guns?

 

[JakeSCH]

This is for sure a tough situation. Tons of things to try, but have you tried removing the mandrel and increasing neck tension to 4 thou?

I will also give a +1 on Lee FCD that was mentioned before. I still cannot believe how 1/8th turns of that the crimp can shrink groups the way they do.

Did you measure CBTO and headspace of the factory rounds? Try and match it with your own?

 

[35WhelenAI]

I don't know this is a fact, however my sense says factories don't worry about neck tension for the most part when dealing with hundreds of thousands of rounds of brass. But every factory load I know comes with a factory crimp.

I can't recall if you've tried to crimp with any method in getting to this point?

 

[Elkhntr08]

You said that Hornady something shot the best, I’d start with Hornady bullets.
I had a 300 Weatherby that I fought with for 2 years, even sent it back to Weatherby. That cost me $200 to find out that it liked 180 TSX factory ammo.
Got the rifle back, pulled some 180 TSX, matched the factory velocity and found a load that shot under .75.
Sometimes, just because you want it, doesn’t mean you’re gonna get it. Work with the rifle not against it.
Don’t remember seeing what model you’re dealing with.

 

[swavescatter]

I thought this was interesting and it made me reconsider my quest for shooting heavies (200gr +) out of my Bergara 300WM. Or just get a 300PRC!

 

[ID_Matt]

Definitely sounds to me like yo have a bad or very picky barrel. It definitely does not like that bullet/powder combo at all. I didn't see in the comments where you mentioned how far you were jumping them. In my experience, berger hybrid types either like 20-40 thou off or as far as 110 off. It does not make sense to me to tune seating depth in .003 increments. Your throat will grow and you'll be right back to square one. I like to find a wide node that is forgiving on both sides so I can load a bunch and not have to worry about adjusting the seating as the throat grows.

 

[long hunter]

Hornady 180 gr. SST, IMR 4831, C.C.I. large mag primers, start with the Hornady loads in their book. R.C.B.S. dies Make sure all case prep is the same for the cases, case length, O.A.L. Also, de-bur the flash hole in the case. I have a Remy 700 LSS in .300 win. Mag. that does well. Also, if you can find a copy of Ken Watters pet loads manuals good place to work from, sometimes old school is the best school.

 

[philcox]

@IDspud if you REALLY want to keep the setup. Might be worth it to have the folks and @Unknown Munitions work up a load for you. Then you could just load that going forward. Not cheap, but much better use of time and $, and reduced frustration IMHO.

 

[WCB]

Figure out what factory load it shot well and by a bunch of it and be done. quit wasting more time and money if a solution already exists.

 

[Harvey_NW]

I might sell my whole set up.

I did the exact same thing with my Bergara. I've never had a single issue loading Bergers in any rifle except a B14. It didn't shoot any combo great, and I personally know of 3 now that require a body collet die to get brass sized enough above the web to chamber properly. No more Bergara's or belted magnums for me.

 

[philcox]

Figure out what factory load it shot well and by a bunch of it and be done. quit wasting more time and money if a solution already exists.

Good luck with that. I had to develop a hand load for my sons 30-06 with the 168g TTSX because finding the Barnes Factory load is like pulling a Sheep tag in California (you essentially can't). In today's climate, if you want to regularly shoot anything, you had better hand load. Just my opinion.

 

[Rifles And More]

It'd be hard for me to dump all those components (H1000 and bullets).

Start with a serious cleaning on the rifle. I mean back to metal. I'm sure someone will be along to tell you it doesn't matter, but it does.

Then, I'd measure the CBTO of the factory load that shoots well and start there with my hand loads. If you can get 1 MOA you've got a great hunting rig.

 

[black dawg]

How many rounds through the rifle? I didnt see where you said for sure what factory load shot good in this rifle, and how many did you shoot?

I would check all screws.

I have had a rifle that would only shoot one load good.....it shot it really good, so I went with it. Most all ammo, factory or handloads were 2 moa or as much as 4 moa. The load that shot was slightly under 1 moa every single time.

 

[HeavyForCaliber]

You said you're happy with the factory load, but not if you tried to duplicate it. You've got the same bullet, but are you loading to a similar muzzle velocity and COAL?

If so you're left with the burn rate. You could pull a bullet and see if you can tell what kind of powder it is.

Also try standard and magnum primers, some powders are particular. My best 7mmRM H1000 loads use standard primers.

 

[IDspud]

The agony continues. I ended up getting so frustrated I paid a guy 400 bucks to develop a load for me.

He said I was pushing the bullet way too fast and dropped it from 77 grn down to 72.

When I picked it up from him I shot a couple of rounds to make sure it was legit. Put two shots on steel at 500 yards within 2ish inches of each other.

I’ve now made two trips to the range since then and it’s doing the exact same thing it was before. A phenomenal group, in groups with flyers, then one complete garbage massive group.

I don’t know what the hell is wrong with this set up. To make it even worse he loaded up 150 rounds of this “good load“ using my components, and had me buy several hundred more bullets. I’m not pulling the shots, especially that bad. Several years, something like $7000, and I still don’t have a solid rifle to get into long range shooting with.

His response… “I think you need to bed the action.”