Now that I have decided to stay with 300Rum, what is in your experience the optimum barrel length( 28, 30, 32)to make use of the powder capacity of the RUM case?

I plan on shooting 200-240gr bullets or at least bullets that length. Cutting edge makes pure copper match bullets that I find appealing.

I am assuming 1-10. Preferences on makers? Does cut rifling really hold any accuracy potential over button? So far I have considered Hart, Lilja, and Broughton. Am willing to consider Krieger and Pac-Nor.

How many groves? 3, 6, 8?

Thanks.

Andy

Written about .30-06 but good info about barrel design. If you have time check out the rest of the blogs. Lot's of good long range info.

Just building a new 300 RUM, using a 30" Krieger 10 twist, not planning on shooting the 240gr VLD type bullets or would have went 9 twist. 6 groove.

quote:

Originally posted by Sam:
Written about .30-06 but good info about barrel design. If you have time check out the rest of the blogs. Lot's of good long range info.

My like didn't post I guess.

http://riflemansjournal.blogsp...ecrets-of-30-06.html

Now, let me begin by saying that I don't have a 300RUM, and probably never will.
That said, there is a ton of good info to be had on the net on this topic. Five minutes with google should easily produce enough articles and information for even the very worst insomniac to read themselves into a boredom induced coma every night for the next twenty years.
In order to sort through the mess, I recommend checking out articles on the Snipers Hide sight, Chuck Hawes and the 6mmBR sight.
I recall reading some interesting articles pointing out that there is a max and minimum barrel length to be found on every rifle load. Research proved that longer barrels yielded higher velocities, but due to barrel harmonics and barrel flex actually yielded worse accuracy.
It would be worth looking into....

quote:

Originally posted by jaybald1:
I recall reading some interesting articles pointing out that there is a max and minimum barrel length to be found on every rifle load. Research proved that longer barrels yielded higher velocities, but due to barrel harmonics and barrel flex actually yielded worse accuracy.
It would be worth looking into....

I was kinda hoping for the experts to come forward with this type of information. Such as what length in their experience produced best velocities without diminishing returns.

Google "bore/barrel length ratio" and aside from detailed discussions regarding naval guns, you will find an article concerning your question done by the SWAT teams of LA. May be of some help to you.

quote:

Originally posted by drewhenrytnt:

I plan on shooting 200-240gr bullets or at least bullets that length.

Thanks.

Andy

Andy,

I'm seeing 308 match bullets at 210 to 240 grains going 1.467" to 1.591".

But most 200s are below 1.4"

Now the copper soilds will be even longer at these wts.

Ugh...Guess I'd suggest narrowing down even picking a bullet before your decide on the barrel.

I built my 300RUM with a 5.5 contour Shilen Select Stainless Match that finished 28". I am getting 3382 fps shooting 185 grain VLD Bergers in front of 96 grains of Reloader 25 with Fed 215 primers. I chose the 12 twist. When I get to rebuild it again I will probably use a Benchmark barrel in a 12 twist 3 groove but it will be a little longer and lighter contour. You can see the pics in "Post your rig" page 5.

God Bless, Louis

Contour and length limitations on accuracy are a fator of the receiver used and the manner in which it is secured in the stock.

You can't necessarily just hang a huge pipe off the front of your existing set-up and not create flex and tension in the receiver and that can negatively affect your accuracy.

I'd discuss that with the gunsmith you intend using.

The rest of the decision depends on how packable that rifle should be and what weight you are aming for. I will never again make these decisions without calculating the finished weight as a function of that decision, including scope, bases, stock, rings, bipod etc.

If you can choose the bullet you can also cut the chamber and choose the twist around that. You can speak to the 'smith again or the reamer guys and the barrel maker regarding twist and groove recommendations.

I'd think 1 in 10, or maybe 9 if you are going to 240gr SMK. My friend's factory Sendero shot 220s just fine (not sure of the factory twist).

Berger has a means of calcuating stability on their ballistics program and you can see the stability factor.

I'd honestly suggest you use that resource too.

Maybe I'm not giving you the answers you want, but I suggest you speak to the guys I suggested. I've got opinions on all of this, but I think you'll get better info from the "experts" than from me!

Everything posted so far has been great. I have looked up a bunch of info I had not considered. So far the barrel maker, the smith, and the stockmaker have all put their two cents in. Now to save the $$. I recently have been having problems with rotator cuff. Copays and deductable are eating away my toy budget rapidly.

I have three .300 RUMs and they all have 26 inch barrels and Vais brakes.

I don't think it much matters; get out and shoot in the wind. When the wind blows at 10 mph, gusting +/- 5 mph, and you are trying to hit something at 700 yards (hopefully not a big game animal) the least of your worries will be accuracy - it will be drift, which is why the mention of high BC bullets.

As much as I love the RUM, all that extra velocity really doesn't give you that much more of an edge in the wind than a .308 Win. But I will take what I can get.

Drew, how are you going to use the rifle?
Is this for shooting paper, or hunting in open country?

I have a 30" on my STW. In a number 5 contour, that about as long as you probably want to go. If you get them too long they can start to whip. If you are going with something heavier then a #5, you can go out to about 32", but that's about where I would draw the line.

Of course the longer the barrel, the further forward your point of balance. If you barrel is too long, you many need to go with a heavier stock to rebalance the rig.

Hope this helps.

The Krieger barrel contour I am considering is similar to their #17 Heavy Varmint except with a .940 muzzle and finish length of 31".

Stock will be McMillan A-5 or Adj A-5. I have been unable to discern the difference...... Would consider the McHale style also-I like that one too.

Drew, sounds like a great set up. You have the right components to go long. I'd go 31-32" if it was my rifle.