300 RUM: 180 vs 200 gr Accubond

[Dinky]

Using the Swarovski calculator, both bullets with 300 yard zero and assumed cross wind of 10 MPH at 700 yards:

180 grain rises no more than 3.3" at midrange.
200 grain rises no more than 4.1" at midrange.

180 grain stated BC=.507
200 grain stated BC=.588

180 grain: Drop=62.2"
200 grain: Drop=73.0"

180 grain: Drift=25.6"
200 grain: Drift=25.6"

180 grain: Velocity=2,161 FPS
200 grain: Velocity=2,051 FPS

180 grain: Energy=1,869 Ft Lbs
200 grain: Energy=1,869 Ft Lbs

(Equal numbers for drift and energy are NOT typos).

So it would seem at first glance, assuming that someone is not going to shoot deer or elk beyond 700 yards (including me ), the 180 grain is all upside--with the only advantage I can see for the 200 grain being its greater sectional density for a hypothetical (and doubtful for me at least) quartering shot on a large animal at 700 yards. The difference of right at a foot of drop from 300 out to 700 seems to militate in favor of the 180 grain.

Recoil would seem to be a wash.

 

[dcederberg]

Howdy, I think your velocity is off, it should be 3161 and 3051 if I am not mistaken. And it looks like you are correct, for me the 180 would also have less recoil.

 

[Dinky]

Thanks for your comments. Actually, those numbers are for velocity remaining at 700 yards.

 

[Barrelnut]

Dinky, what's the muzzle velocity or both bullets?

I ran some general numbers in another calculator and the 180 seems to have 2" flatter trajectory at 700, 1.5" more drift, and about 150 LBs less energy at 700 than the 200 Gr one. Which I think makes sense since the BC is different.

 

[Dinky]

Barrelnut: sorry, I meant to include muzzle velocity. For the 180 grain, I used 3428--which may be more than I end up using--but which was chronographed by my gunsmith, with a 27 inch bbl on my rifle.

For the 200, I used 3100, which is a bit ambitious, but, I think doable.

 

[Deleted member 46119]

In my 300 RUM 3100fps + with 200grns and over projectiles is a diddle. To easy.
I never went to 3400fps with 180grns, it probably can but I didn't.

I use JBM and Strelok for my calcs. Matches reality better for me.

In my charts I get:
4" difference in wind at 700 yards.
300 FPE difference, of course the 200grns has more.
Drops are close enough to be considered the same at 700 yards
Using a 10" vitals zone both are well withing the vitals with no adjustment to 400 yards and more.

Find out which one the gun shoot better and go with that.

 

[Lefty7mmstw]

3300 fps with a 180 in a 300rum is easy; 3400 fps and even with a 27" bbl. you are pushing it a bit. I've never chrono'd 200's in my rifle (though retumbo does like the sierra's) but I top at a bit over 3100 fps with hdy 190's and about 3000 fps with 220-225 grain pills.
A better (and more realistic) comparison for the 300rum is a 180 at 3300 fps and a 220 at 3000 fps imo.. If you are set on the 200's 3100 fps can be done with the right powders.

 

[Dinky]

Thanks for the information, Lefty and Seaman. Right now, I have no 200s to work with and availability is not good. I have a large inventory of RL 25 and 5 pounds each of RL 22 and IMR 4350. Lefty: what is your opinion of those powders for 180/200 grains? I also have 250 Barnes TTSX 230 gainers to hammer Texas whitetails! My gunsmith got an average of 3936 with those in front of 104 grains of Reloader 25.

 

[Lefty7mmstw]

Thanks for the information, Lefty and Seaman. Right now, I have no 200s to work with and availability is not good. I have a large inventory of RL 25 and 5 pounds each of RL 22 and IMR 4350. Lefty: what is your opinion of those powders for 180/200 grains? I also have 250 Barnes TTSX 230 gainers to hammer Texas whitetails! My gunsmith got an average of 3936 with those in front of 104 grains of Reloader 25.

I'm loading 93-94 grains rl25 with the 180 hdy for a banjo string trajectory mid range load in my 300rum. It was 3280 fps already at 93 grains the last time chrono'd. I think rl22 could be made to work but may top before 3300 fps. I'd stay to an '06 based cal. (270, 280, 30-06) with the 4350.

I hope you meant 130, not 230 ttsx

 

[Buttermilk]

My Rem 700 300 RUM Factory 26" bbl will do 3372 FPS with the Nosler 180 AB pushed by 97.0 gr Retumbo. Load books say I can go up to around 102.5 gr but I haven't gone there yet.

I have also loaded IMR4350 with excellent accuracy using the Nosler 150 AB and 180 AB. In fact, Nosler's manual states their technicians observed near bench rest like accuracy when using IMR4350 and medium weight bullets. My testing in my gun shows good accuracy with good velocity.

 

[Dinky]

I actually bought the IMR 4350 for use in the 300 Winnie, specifically for use with the 130 TTSX bullets. I could not find any load data at all for the RL25 I had squirreled away. As they say, sometimes no answer is an answer!

 

[AZShooter]

I got the 200 gr accubond to go 3175 with a 27" lilja using RL-25. Shot several elk with it and only found one bullet in an animal which was a diagonal body shot traversing at least 25" at 560 yds. If I were to again use the 30 cal accubond it would be the 200 grainer.

I switched to the 230 gr Berger because the issue with the longer shots was wind drift. Even at the lower velocity of 2975 fps the Berger superior in drift and retained energy.

 

[Dinky]

AZ: 3175 would definitely weigh in favor of the 200. Do you have a feel yet or have you shot that load enough to give you an idea of barrel/throat erosion?

Does anyone see 200 Accubonds available occasionally ?

 

[AZShooter]

This barrel would be a poor one for judging how long a 300 RUM barrel lasts. It was listed on Lila's site with a reduced price. It is a 27" SS #5 fluted with a 1 in 12 twist. I first used it as a 30 BR putting 450 rounds through it. Then I had it made into a 300 RUM and added a VAIS brake. It has an additional 673 rounds through it when I pulled it off. It definitely takes time to clean but still shot quite accurately. I removed it to put on a 24" rechambered 300 win mag barrel to try the new 230 berger when I realized I had forgotten that the Lilja didn't have enough twist for the 230.

I just got out the bore scope and inspected the old barrel. It has cracks and crazing for about 9 inches up the barrel. Throat has what looks like tiny chips removed from the surface of lands and grooves. Not sure I will ever use it again. I Am saving it should I get a wild urge to make it a 338 EDGE. Dan Pederson could re-rifle it for far less than buying a new fluted #5 SS barrel.

Last load I tried in it for grins was the Berger 168 Classic hybrid with RL-22. It used to shoot the 168 Sierra MK at 3550 with 95 gr of RL-22 back in Oct 2008. Got up to 96 gr of RL-22 with 3530 fps.

The current 24" rem takeoff is getting 2975 with 100 gr of RL-33 and the 230 gr match target hybrid. The rifle is very handy to carry for my elk hunts I see no reason to change it.