Question about twist rates & bullets

[freebird63]

My 300 RUM seems to shoot 230gr berger hybrids very well at 100 yards, I forgot to mention my factory barrel has a 1-10 twist and yest its a remington, but when I went out to 200 yards the groups opened up.
On the berger box it says 1-10 twist rate, but when I go to berger's website it says optimal twist rate of 1-9
This is my hunting gun and have a very important mule deer hunt coming up in November, so between work, scouting and dialing in rifle....crunch time.

 

[Jerry M]

Find another bullet that is more accurate in your rifle at the longer ranges where the shots are anticipated. That seems to be the most timely solution than rebarreling.

 

[freebird63]

Thats just it, have tried 200gr ELD-X, 200gr accubond, berger 200.20X and none of these seem to want to shoot.....I tried seating to SAAMI spec's and tried seating to just barely fit in mag box.
I don't really want to go below a 200gr bullet. The next ones maybe the barnes 200gr LRX or 210gr long range accubond?
I'm really scratching my head with this gun.

 

[coop2564]

When you shot further was it windy? Most the time if a rifle is stable at 100 it does well down range as well, unless other factors like wind, mirage, etc come into play.

 

[Jerry M]

Thats just it, have tried 200gr ELD-X, 200gr accubond, berger 200.20X and none of these seem to want to shoot.....I tried seating to SAAMI spec's and tried seating to just barely fit in mag box.
I don't really want to go below a 200gr bullet. The next ones maybe the barnes 200gr LRX or 210gr long range accubond?
I'm really scratching my head with this gun.

Wow that is a problem. Is the barrel accurate with match bullets or any other weight bullet? When you say open up at 200 what kind of groups are you getting? You may be looking at a rebarrel job. That sucks.

 

[freebird63]

At 100 yards I could put 5 holes in the target the size of a quarter. At 200 yards they open up to 4 inches

 

[freebird63]

No wind or mirage, I go out very early to avoid that

 

[SLV Shooter]

What kind of optic set up do you have on your rifle. Are you shooting off a bench or bipod?

 

[Mikecr]

Not a twist rate or bullet problem

 

[freebird63]

Shooting off a bench and using an athlon ares 4.5-27X50 BTR
So not a twist rate or bullet problem. Am all ears. What's your answer mikecr

 

[eshorebwhntr]

I've posted this several places recently but I guess it applies here too.

In recent years bullet manufacturers have realized that Ballistic Coefficient (BC) is related to twist rate. You likely have an older box of 230's before they were updated. In most cases there is an optimal twist to maximize BC and a minimum twist required to be stable. I agree with Mikecr...I don't believe what you're seeing is twist or bullet related. Your bullet is likely stable but a few % lower than the advertised BC.

A friend I reload for has a factory Remington 300 RUM 10 twist and we got it shooting a very good group this spring with the 215 Hybrid. He shot it most of the summer and noticed the accuracy was degrading and called me in a panic thinking the throat was burnt out. I measured it and it had eroded .024 in 250 shots or so. He hadn't cleaned the rifle so I started there.

Patches were dark dark blue. Let it soak overnight and get all the fouling out. The next day it was right back to sub .5 moa without any changes to anything else. Not saying this is your problem but it might be a place to start.

 

[shooter72]

The 230's fly very well from a 10 twist provided you have a little speed (2700 and up) even if your under than they will typically be stable short but break down out long - say 900 +
I have shot them very successfully from many 10 twist WSM's and RUM's.

 

[RockyMtnMT]

I'll make you the deal that we give to all of our customers. Purchase a box of our bullets and if you can't get them to shoot to your standards we will buy them back.

We have done a lot of shooting with the 300rum and have load data to get you started. I believe we can have you load developed and sighted in out to max range in less than 25 rounds as long as there is not something wrong with your rifle.

PM me if you would like to talk about what bullet fits your needs, or in the open forum. You can call if you like and I would be happy to talk about it on the phone. 406-261-0010

Steve

 

[Dosh]

63, have you tried the 215 Berger?