Which 80's did you shoot? I'm going to resume LD on a Varget/80gr MK load this spring, and I'm near 2 grs hotter than my go to 73gr load already. Digging the BC's, and the faster the better, but at the expense of brass life... I may end up pulling it back into the slow lane and riding the wave gently to get more use out of my cases. Are you constantly doing LD in new cases?
F-TR .223 loads
- Thread starter shootmore
- Start date
Which 80's did you shoot? I'm going to resume LD on a Varget/80gr MK load this spring, and I'm near 2 grs hotter than my go to 73gr load already. Digging the BC's, and the faster the better, but at the expense of brass life... I may end up pulling it back into the slow lane and riding the wave gently to get more use out of my cases. Are you constantly doing LD in new cases?
shootmore
Silver $$ Contributor
Krieger 30" 1:6.75
Ned Ludd
Silver $$ Contributor
I have one .223 that is dedicated to the Berger 80.5s; it doesn't have sufficient freebore to load the 90s optimally. I will usually do preliminary load development in prepped virgin Lapua .223 brass. I open up the necks of virgin brass with an oversized (0.223") expander mandrel, then size them all back down with the appropriate bushing (0.248") to give ~.002" neck tension/interference fit. I find that brass prepped in this way gives far more consistent results than brass straight out of the box, because neck tension in non-prepped virgin brass seems to be all over the map in my hands.
Prepped virgin brass usually gives very consistent results. I would not hesitate to use it in monthly club matches, although I usually prefer to use fire-formed brass for more critical matches. I generally find it necessary to adjust the charge weight down once the brass is fire-formed in order to keep the velocity consistent with the load optimized in the virgin brass. Presumably, this might be because some small amount of the combustion energy goes into expanding the virgin case, especially in the shoulder region, to fit the chamber dimensions. In my hands, the shoulder of .223 brass moves about .006" to .008" on the first firing. Because I only push the shoulder back ~.001" to .002" when re-sizing, the cases are much closer to the internal dimensions of the chamber after the first cycle. It is not uncommon to observe an increase in velocity of anywhere from 10 to 20 fps in fire-formed brass versus prepped virgin brass. That increase may or may not be enough to push the load out of the "optimal" window, you really just have to test to find out. More importantly, it may be enough to shorten the lifespan of the brass when running H4895/90s at ~2850 fps. Typically, I find a decrease of 0.1 to 0.2 gr in charge weight is sufficient to bring the velocity with fire-formed brass back down to what it was in virgin brass. Nonetheless, this is something you will want to test yourself, and make any necessary adjustments based upon your own results.
foxguy
Gold $$ Contributor
Good info, Thanks.
I believe it’s 28” but it might be 30”
What kind of speeds are you getting with that load? 23.7- 23.8 grs tightened up for me with a 22" tube. The next sweet spot was alot higher than I expected.
88Gr Hornady ELD-M, 23.5 gr H4895, Lapua Brass, CCI BR-4. 2835 FPS out of a 26" X-calliber barrel chambered in 223 rem ISSF. Shoots in the 0.2 on a good day 0.3's - 0.4's on a bad day. Brass is still going strong too. tight primer pockets after 3 firings on brass that was already used in my old FTR 223 (with a lighter load).
shootmore
Silver $$ Contributor
After digesting all this great info, I reviewed the Varget Ladder and nodes, found that i had choose the tightest node (3 progressively larger loads/shots), about 1" vertical at 500 yards, also was the hottest at load at 2,900fps.
I'm going to OCW the next best node (3 progressively larger loads/shots), about 1.7" vertical at 500 yards, 2,780fps. Which was reported as a good fps range (Savage with Bergers etc.).
Also going to try the Berger 90's for the N140 and both Varget loads. Now if I can get it done before the John Martin cup maybe I can win the HM instead of the Expert class or at least beat my 12 year old Geez!
I'm going to OCW the next best node (3 progressively larger loads/shots), about 1.7" vertical at 500 yards, 2,780fps. Which was reported as a good fps range (Savage with Bergers etc.).
Also going to try the Berger 90's for the N140 and both Varget loads. Now if I can get it done before the John Martin cup maybe I can win the HM instead of the Expert class or at least beat my 12 year old Geez!
MikeMcCasland
Team Texas F-T/R
Not sure if 24.6gr of Varget behind a 90 VLD is considered "nuclear" but with BR4 primers you can tell it's right on the edge of wanting to flow a bit; with the thinner cupped CCI 400 primers you get slight flowing back into the firing pin.
No flattning or gas leakage that I've seen.
Ned Ludd
Silver $$ Contributor
I wouldn't exactly call the 90 gr loads with H4895 at ~2850 fps for F-TR "nuclear", but they're not "mild" either. For my ~2850 fps H4895 loads, QuickLoad predicts a pressure of approximately 57K psi. SAAMI spec maximum average pressure for .223 Rem is 55K psi. So they're certainly running above SAAMI max by ~2k psi, which fits pretty well with the poor brass life. Hard bolt lift is not an issue, but the primers may appear very slightly flattened. Neither gas leakage around the primer, nor bolt face erosion appear to be a problem and are not any different than that observed in my .308s (which is to say minimal, at most). My .308 loads have predicted pressures in Quickload of about 59.5K to 61K psi, which is slightly below the SAAMI max of 62K psi.
For comparison, people running 200s in their .308 F-TR rifles at the high node (~2700 to 2720) fps are likely experiencing pressures somewhere in the range of about 64K to 66K psi, or approximately 2K to 4K above SAAMI max. The obvious difference between the two cartridges is that F-TR shooters pushing heavies in the .308 are using SRP Palma brass, which has substantially more metal surrounding the primer pocket and can clearly take the increased pressure for longer periods without dramatically affecting the primer pockets. Put simply, pushing a 90 gr bullet in excess of 2800 fps out of an F-TR rifle with 30" barrel is simply asking a lot of that cartridge, and the casehead region surrounding the primer pocket is clearly the part of the case that most often exhibits the effects first.
For comparison, people running 200s in their .308 F-TR rifles at the high node (~2700 to 2720) fps are likely experiencing pressures somewhere in the range of about 64K to 66K psi, or approximately 2K to 4K above SAAMI max. The obvious difference between the two cartridges is that F-TR shooters pushing heavies in the .308 are using SRP Palma brass, which has substantially more metal surrounding the primer pocket and can clearly take the increased pressure for longer periods without dramatically affecting the primer pockets. Put simply, pushing a 90 gr bullet in excess of 2800 fps out of an F-TR rifle with 30" barrel is simply asking a lot of that cartridge, and the casehead region surrounding the primer pocket is clearly the part of the case that most often exhibits the effects first.
Linko
Silver $$ Contributor
I am planning a new build and I am thinking I will use the 80.5 Berger with .125 freebore, instead of the 90's so I can get more life from the brass. I don't expect to shoot in competition any time soon so I thought this might be a good choice.
Or should I chamber for the 90's with .169 freebore and just shoot with lower velocity?
I'm just shooting for fun. (200- 500yd)
Or should I chamber for the 90's with .169 freebore and just shoot with lower velocity?
I'm just shooting for fun. (200- 500yd)
Ned Ludd
Silver $$ Contributor
Damon - FWIW, in my hands, even running 185 loads in Lapua standard .308 brass (LRP) that were predicted by QuickLoad to be only at pressures of 60K to 61.5K psi (i.e. under SAAMI max) would kill the primer pockets in 4 to 5 firings or so. As you know, Palma brass would take those pressures almost indefinitely. Perhaps the .223 case primer pockets are slightly more resistant to opening up than .308 LRP brass from a relative viewpoint. However, poor brass life is still a sore point with F-TR shooters using the 90s at the 2850 fps node. The thing is, they shoot so ridiculously well at that velocity that it's mentally difficult (for me at least) to purposely slow them down.
Linko - with a 30" pipe, the 90s over Varget should tune in somewhere around 2820 to 2830 fps, or about 20 to 30 fps slower than an optimized load in the same rifle with H4895. I have recently been trying other powders for this very reason. H322, which is really quite fast for a 90 gr bullet, also looks to tune in around 2830 fps. Although I have not tried them yet, there are certainly other powders such as IMR4064, IMR4320, IMR8208XBR, and probably a few others that will likely tune in at velocities from perhaps 20-30 fps, to as much as 50-60 fps (or more) slower than a tuned H4895 load in the same rifle. My suggestion would be simply to find a powder for which an optimized load gives you a velocity somewhere in the 2775-2825 fps range. That would certainly help with pressure and brass life, but you wouldn't be giving up so much performance that it would totally defeat the purpose of using the 90 gr bullet.
Even at only about 2700 fps, the 90s will shoot well inside most of the 80-grain 0.224" offerings, at least in terms of predicted wind deflection. The BC of the 90 VLD is simply that much higher than the next lower weight class of bullets. However, it's not solely an issue of maintaining equal or slightly improved performance relative to an 80 gr bullet, it's also about not giving up too much ground to the .308 F-TR shooters you will be competing against. Finding a powder that would tune in with the 90s at 2775 to 2825 fps or so in a 30" barrel would would be ideal. It would likely increase brass life noticeably, without giving up too much performance.
Damon - FWIW, in my hands, even running 185 loads in Lapua standard .308 brass (LRP) that were predicted by QuickLoad to be only at pressures of 60K to 61.5K psi (i.e. under SAAMI max) would kill the primer pockets in 4 to 5 firings or so. As you know, Palma brass would take those pressures almost indefinitely. Perhaps the .223 case primer pockets are slightly more resistant to opening up than .308 LRP brass from a relative viewpoint. However, poor brass life is still a sore point with F-TR shooters using the 90s at the 2850 fps node. The thing is, they shoot so ridiculously well at that velocity that it's mentally difficult (for me at least) to purposely slow them down.
My experience exactly. I always reckoned that for serious F/TR competition at mid/long-ranges a brass life of at best five firings was a cost of doing business. As I had two 223s at the time, the latter set up for short-range with lighter loads, I simply transferred my L-R brass to it after four full-house firings in the L-R rifle. That way I got at least eight firings in total from a case.
Back in the very early days of F/TR when there was little experience of 223 with 90s and no consensus even on the twist rates needed, I ordered a Medium Palma profile Bartlein 224 blank in 1:7.5 from the UK importer. It was for a Savage LRPV single-shot sporting rifle then in 204 Ruger that had shot incredibly well in factory out of the box form, but whose barrel was getting tired. Bartlein was the hottest of hot barrelmakers among BR and F competitors at that time and with a relatively unusual profile / twist combination, delivery took so long that when it eventually turned up around two years after placing the order I'd given up on it. By then we knew you needed at least 1:7 twist for optimal use with 90s. What to do with it? Working on the 'what the hell?' principle we went ahead as originally intended, chambered it with the same long FB reamer I'd used in my L-R rifle, exact FB unknown but likely ISSF + twenty or thirty thou' and tried it with mild Viht N150 loads with the old since discontinued Berger 90gn LRBT bullet. Because it was going into an H-S Precision sporting rifle stock not a proper F/TR rig, it was cropped at 26-inches OAL in the build. (Viht N150 works well in 223 with 90s, I'd found long before but won't give as high MVs as VarGet, Re15 and similar as you can't pack enough into the case.)
A node was quickly found at only 2,650 fps and it shot really, really well at short distances. I picked up a few wins and lots of second places in our 300 yard matches against very good 308s. It shot well at 500 too, but on a windy range, it was giving away too much ballistically in 500/600 yard matches to my 90 VLD/2,900 fps L-R 223 load or the 308s which were by now pushing Juggernauts out at 2,750-2,825 fps. So, with a happy 90gn bullet / barrel combination, mildish loads - in this case milder still than your proposal - are well worth pursuing. Of course, competition standards have risen considerably in recent years, so pursuing the ultimate rather than plain very good has become the norm now.
shootmore
Silver $$ Contributor
Makes a lot of sense. Where do we get oversize mandrel to open up the virgin necks? What size od?
Upgrades & Donations
This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.
Click Upgrade Membership Button ABOVE to get Gold or Silver Status.
You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.
To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.