Mid Range F T/R 223 Rifle/Load

[r bose]

T-REX, I just installed a 31" Heavy Palma profile barrel on my rifle. I like the little extra weight and stability it provides. Most guys shooting prone I know, regardless of caliber, use a medium or heavy palma contour barrel at 30'-32' long.

Also, longer barrels equals longer sight radius's and that's a big plus to a prone shooter. I want my front sight as far out as possible.

As you say, the advantages of the longer barrel: stability, velocity, and sight radius are obviously significant and that shows with most folks in the 30 to 32 inch range as you have observed. Here is what I am thinking for my application; at my age weight is becoming an issue and I need to keep the weight within my limitations and I may have to compromise some on barrel length to do that. Since I am shooting in the Any/Any category with a scope the added sight radius is not important. What is important is to have a barrel length that gives sufficient velocity to take advantage of the capability of the bullet. For example, what would be the velocity difference between a 26 inch barrel, a 28 inch barrel, or a 30 inch barrel with the 90 grain bullets? For me the reduction in weight might be worth the trade in velocity. Also it may be that to take advantage of the 90 grain bullets there is a barrel length that is needed to get the velocity to justify going from the 80s to the 90s. Your thoughts?

T-Rex, I'd use a lighter barrel before I'd go with a shorter one. If weight is a concern, use a Light Palma Taper Barrel but keep it at 30" to maintain velocity.

 

[chkunz]

Everything you said is essentially correct except for "good" brass life. I initially prepped ~450 pieces from the same lot, so I can't really say yet how many firings it will get. QL predicted pressure is ~57.3K psi and in my hands, if you go much higher than that the primer pockets will go south pretty [very] quickly. I'm guessing that barrel life ought not to be too bad, which is to say maybe 2500-3500 rounds. Could be a little bit more, it's hard to say just yet. As mentioned, I could achieve velocities above 2900 fps with H4895 relatively easily, in other words case capacity is not limiting. However, the predicted pressure was ~59K psi and brass life was pretty much nonexistent. I think where the load is currently, I will likely get at least 4-6 firings on the brass. That may be considered quite low for some, but I'd be perfectly happy there. Based on my [unscientific] barrel life estimate above, that would be fairly close to the end of the barrel. I have another identical barrel already chambered at .169 freebore, but as I mentioned that is really much shorter than it should be, especially with the bullets seated at ~.015 off. I will probably throat out the replacement barrel to somewhere on the high side of .200" freebore. That should go quite a way toward extending brass life as QL predicts it will drop the pressure down to ~ 53-54K psi.

Performance so far has been very good IMO. I have not experienced any major difficulties loading the 90s. The only hiccup really was that I thought I would need to seat them into the lands due to the secant ogive and all, so that is where I started. However, I was pleasantly surprised to find out subsequently that they actually shot better from about .011"-.017" off the lands, so that is where I'm loading them. I believe that this has something to do with the very tight (.2242") freebore cut by the ISSF reamer. When I first used a Stoney Point OAL gauge (Hornady) to measure the distance to the lands, I felt a distinct "stop" as the bullet was initially pushed in. But it was far short of where I knew it should be according to the reamer specs. With a little more pressure, the bullets would then slide in quite a bit further, albeit with some slight resistance until a true "hard" stop was reached. As it turned out, that was the tight freebore. It is so tight, the bullet just doesn't have anywhere else to go but straight into the chamber and may be why they don't mind being jumped in my hands.

You can certainly run the numbers yourself, but at 2850 fps, I roughly estimate the BC of my pointed 90s is .290 (G7), representing about a 3% increase from pointing. My 185 Juggernauts are ~ .292 BC, close enough to practically be the same number, but only moving at ~2750 fps muzzle velocity. On paper (JBM Ballistics), the 90s will shoot inside the 185s by 0.3 MOA in a 10 mph full value wind at 1000 yd (6.7 MOA vs 7.0 MOA). I believe this estimate matches very to my shooting experience with both rifles. As far as the 80-somethings, even at 3000 fps they're over 2 MOA behind (8.8 MOA)...it's really not even close. The BC advantage of the 90 VLDs is simply too great to overcome by increasing velocity of the 80s, at least in terms of velocities that can realistically be achieved.

So how would I characterize the differences? I believe that if you can get the 90s working with good precision in the 2800-2850 fps velocity range, you will be shooting on a very equal or even slightly better basis (in terms of wind deflection) to .308 shooters using most bullets up to the approximate BC range of 185 Juggernauts/Hybrids. The significant lack of recoil might even be a slight additional edge to the .223. You will be at a slight to moderate disadvantage to .308 shooters using 200 or 215 Hybrids in terms of wind deflection. You will have a significant edge in windage over someone using 80 gr .223 bullets. As always, these are merely estimates on paper and relative shooter wind reading ability can always come into play. However, I think the above is a pretty fair assessment of where the ballistic potential of a .223 F-TR gun set up to shoot the 90 VLDs will stack up relative to other commonly used .223 Rem and .308 Win bullets. For me, there is just something special about shooting the little .223 Rem with its minimal recoil at 1000 yds. I could certainly get myself a .308 setup in which to shoot 200 or 215 Hybrids, but right now I'm limited to shooting 185s. So I'm not really giving up anything by shooting the .223.

This is all really amazing and answers my questions, thanks. Today F Class is doing for the shooting sport what bench rest did in the 1940s, 1950s and 1960s pushing the accuracy technology to new levels. I watched the AR in 223 become the dominant rifle in National Match Competition (aka XTC). I have shot the M14 in XTC since ~1980 and still shoot it but it can not compete with (beat) the AR in that sport. I have been shooting the AR at 600 yard mid range matches and it is a pleasure to shoot. Recoil is a factor no matter how tough you are. I have shot my 1000 yard tube gun in 260 Remington at 600 yards and it does very well but is not as pleasant to shoot and at my age, the recoil and weight are becoming significant factors. That is why I am seriously considering the 223 in a tube gun for 600 yard mid range matches. I had not considered the 223 for 1000 yards but based on your information it could keep me in that game for a few years yet. The little 223 has the potential for doing for F-T/R what it did for XTC push out the 30 cal. Take care, Clyde

 

[chkunz]

This is all really amazing and answers my questions, thanks. Today F Class is doing for the shooting sport what bench rest did in the 1940s, 1950s and 1960s pushing the accuracy technology to new levels. I watched the AR in 223 become the dominant rifle in National Match Competition (aka XTC). I have shot the M14 in XTC since ~1980 and still shoot it but it can not compete with (beat) the AR in that sport. I have been shooting the AR at 600 yard mid range matches and it is a pleasure to shoot. Recoil is a factor no matter how tough you are. I have shot my 1000 yard tube gun in 260 Remington at 600 yards and it does very well but is not as pleasant to shoot and at my age, the recoil and weight are becoming significant factors. That is why I am seriously considering the 223 in a tube gun for 600 yard mid range matches. I had not considered the 223 for 1000 yards but based on your information it could keep me in that game for a few years yet. The little 223 has the potential for doing for F-T/R what it did for XTC push out the 30 cal. Take care, Clyde


Clyde - best of luck with that...I think you would like shooting a .223 very much. In fact, it sounds like your biggest concern might need to be how much of your "nest egg" the new tube gun eats up ;D. Feel free to PM me if you have other questions; I'll be happy to help if I can. The good news is that there are a number of shooters here at A.S. that are well-versed in using the 90s for F-TR...it's a good resource.

Thanks so much, I need time to digest all of this great information. I will stay in touch and thanks again for sharing such great information. Take care, Clyde

 

[ebb]

Are 80 or 90 grain bullets the way to go for 600yds? I have no idea I am just asking. I built a 223 several years ago on a 9 twist barrel and the heavy bullets are way beyond my twist. Ive been shooting 73 grain Bergers, and have only shot 600 with it once and had many hits on steel at Manatee. I have a box of 75 grain Bergers and intend to try them in the 9 twist barrel, some say they will work others say they wont. My mentor always says "you only have 2 friends in long range shooting, speed and BC." My setup leans toward speed cause my barrel wont allow BC, most of the rest of the posters here seem to be leaning towards BC. I understand it when going to 1000yds, maybe not at 600.

 

[boltman13]

Ebb I feel your pain shooting a 1:9 twist in 223 in midrange. My rifle shoots Berger 70's very accurately, but the wind eats that bullet up. Hornady 75 non Amax bullets handle the wind a little better but are not as accurate in my rifle. Over the winter I plan to rebarrel with a 1:7 twist so I have more choices. I have struggled with the velocity vs BC issue for years, in HP, long range and midrange. I am still not sure which way is best for me but am starting to lean more toward heavier bullets with higher BC.

 

[Delaware_Ken]

I shot this score at 500 yards with my 223 7 twist Savage. 80 grain Bergers get the job done for me.

 

[chkunz]

30" Bartlein Barrel
1:6.5 Twist Barrel
80 SMK
23.2 grains of IMR 8208.
2850 fps.

I can shoot the Berger 90's, but my rifle is throated for the 80's, so to shoot the 90's I have to reduce the powder load due to setting the bullet so low in the case. Accurate, but I lose about 100 fps.

Thanks for the response. I notice that you are shooting a 30 inch barrel and that is probably the right thing to do for you since you are shooting from a rest. But I am wondering how much velocity increase you get for the last four inches of barrel? Since I am a sling shooter the weight and balance matter more to me than for your application.