Is anybody successfully shooting a Hornady VMAX 60gr in a 1:9 twist CZ-527 varmint? I am using H335 and Lapua brass with a SR Match primer and can't pull finer than 1.5" group at 100 yards.

I have shot .5gr intervals from 22.5gr to 24.0gr with bullet seated .01 off the lands. I have printed 5 shot flat lines to 5 shot circles but nothing tightens up to a fine bug hole.

I guess COL is next or go heavier than Hodgdon Max listed in their guide. I have no primer flattening or any other pressure signs.

Is anybody having any success with this bullet in a CZ-527 .223 Varmint 1-9 twist.

thanks in advance. rch

I've loaded the similar 60 grain Nosler Ballistic Tip for a friend in his CZ 527 which shoots it well, however, I believe his is a 1-12" if I recall correctly. Although I don't have a record immediately in front of me at the moment, I did use H335, but probably more like 25 grains. I have not found slight increases of H335 above the highest load in most listings to be problematic in the .223.

Stonecreek, the online Hodgdon site shows 24.0 gr as max for H-335 with a 60 gr VMAX. After reading your reply, I got off my Lazy A** and pulled my Lyman 49. It shows 25.8 gr as max. I had NO pressure signs at all with the Hodgdon max charge of 24.0 grains so I am comfortable with your observation.

More powder. I will set up 24.5, 24.8, 25.0, 25.2 for openers and still have the last .6 gr increase in my pocket.

Thanks for reminding me that the web may not supply the best answer. rch

My CZ shoots the Berger 73 grain 1 1/2 " at 200 yds. 4 shots DP 74 surplus.
roger

bartsche, that's what I was hoping for when I bought this rifle for my 66th birthday present 3 weeks ago. Thumbhole Varmint model. I will have to look up your surplus powder because I am not familiar with it.

thanks for the encouragement.

v/r rch

The burning rate seems to be between BL(C)-2 & RL15.
roger

A 60 grain Vmax is ~0.862" in length. Assuming you have a 24" barrel on your .223 CZ 527, you are looking at a velocity of 3150 to 3200 fps at reasonable (56k psi) pressures. I came up with a 1 in 11" twist minimum to stabilize that bullet at a velocity less than 3350 fps. With the 527 Thumbhole Varminter, you should have a 1 in 9" twist barrel so I don't think twist is the issue.

I don't use H-335 with .224" bullets over 55 grains, but that is me. So if it were me, I would be trying a different powder. The Sierra and Nosler book accuracy loads are usually pretty good suggestions for a powder and a particular bullet that will work with a cartridge. I have had good luck doing this over the years. The bullets are different so the pressures are different, so obviously you can't use the same powder amounts. You have to start low (80-85%) and work them up, a little lower than any other book load (90%).

The 5th Edition Sierra accuracy load for their 60 grain bullets is 23.2 grains of Accurate 2015 in a bolt action and 24.7 grains of Vihtavuori N135 in a gas gun (AR-15). The Sierra 4th edition has 25.0 grains of Winchester 748 for a 60 grain in a bolt action. The 5th, 6th, 7th, and 8th edition Nosler books have 22.5 grains of Benchmark as an accuracy load for their 60 grain bullets. They are likely not re-testing, and just reprinting the information, or they could really, really like that one. BTW: if you cross reference those powder weights in the Hornady book for the 60 grain Vmax, some of them are higher than the Hornady maximums! I'll say it again: you need to work up the load.

The Lyman 49th Edition has several loads for the 60 grain Vmax bullet listed. Their accuracy load is 24.5 grains of Accurate 2015 with a COL of 2.260". That load's stated velocity is 3217 fps, and its pressure is 52,000 CUP (note the CUP there not PSI). If it were me, I would be looking at Accurate 2015 as a powder; it shows up as a top choice in two different books for that bullet weight. It is a faster powder than I would have expected to work, but if it works...it works.

It might sound obvious, but if the rifle is new, shoot a group with something that shoots well in .223 Rem with either 1 in 9" twist or 1 in 12" twist barrels.

Try 27.3 grains of H-335 with a CCI BR4 primer with either a 50 grain .224" Sierra Blitzking or 50 grain .224" Hornady VMax at either standard OAL or 0.020" jump to the lands. Use your Lapua brass as it is good stuff, or plain old Winchester (it shoots with little to no prep).

If you don't want to reload different bullets, get a box of Federal Gold Match with the 69 grain Sierra Matchking bullets. I have yet to see a 1 in 9" twist .223 Rem rifle that didn't shoot MOA or better at 100 yards using them if the rifle can shoot.

Finally, it is entirely possible that I fat-fingered something when entering the load information. I don't think I did, but it is possible. Double check the information against the sources I quoted.

(edited to add fat finger caveat)

Webfeet, what a great response. Very complete sharing of your notes.

I did buy a box of Federal-GM with the 69gr MK bullets to initially "register" the gun. These will shoot a consistent 3/4" group (raw edge to edge, not adjusted).

The factory target with the rifle was a bug hole, but, only 50 yards and shot with 55 gr.

I have a fairly broad range of powders available to me. I have several bullet options as well. I will run the 335 on up a bit. I just loaded 6 more sets running from 24.3 to 25.4 gr. If I find nothing in the set, I will change powder. I of course Don't Have the powders that you listed. I do have TAC, BL(c)-2, Varget, and the LT series. I have an AR-platform full bull varmint gun witk 24" in 1-8 that loves VARGET with the 60 hornady. I could try this next. I will report when I find something that works.

Again, thanks for all the information you sent. I will give the 50 gr loads you list a shot. (pun intended)

thanks rch

If I have Varget, I would use that before any of the others. It just flat out works in both the .223 and .308 in my target loads. As a side, I have not had much luck with BL(C)2 and super accuracy. It puts bullets downrange, but there are better choices. I would leave that for last.

I am 95% certain Varget will meet this need, and it would be my next choice. The Hornady books have 24.9 as a max load for the 60 grain V-Max. Lapua .223 brass has a bit less case capacity than some other brands like the Winchester I mentioned. My guess is that somewhere around 23.5 grains of Varget will be a good number.

I had a look at Quickload for Varget and ADI AR 2208 (Varget is rebranded ADI powder). It had 54,566 psi of pressure with 24.9 grains of either power with that 60 Vmax. I like round numbers for ease so I ran 25.0 grains as well. It gave 55,329 psi, and neither 24.9 or 25.0 are pushing anything in a bolt gun and a cartridge with a pmax of 62,366psi. Different story in a gas gun, but the discussion is about a CZ-527.

It it were me, I would use 25.0 grains (Varget) as a max. I would load 10 at 23.0, 10 at 23.5, 10 at 24.0, 10 at 24.5, and 10 at 25.0 grains That gives me 50 rounds to find the accuracy nodes in what should be a sweet (and safe) spot in the pressure curve.

Caveat: not saying you should do this, but this is what I would do. My CZ-527 is not your CZ-527, my powder lot is not your powder lot...blah blah blah.

Only thing I ever noticed about Varget is that it tends to heat up my barrel quickly.

Somebody said one time that RL-15 would match the loads but run a cooler barrel. The next guy then said "yeh, but the RL's are heat sensitive".

I have been at this for 50 years (first reloader was a lee loader kit in 30-30).

Back to here and now, I will load some varget to try this weekend as well. Just cause I am cheap, I use 3 round sets for running up the ladder. I go to 5 with what looks promising from the 3 round sets. I only go to 10 when I am pretty sure that I am going to like it and want to confirm it continues with a set.

Again, thanks for all the great information you are sharing.

rch

I bought a CZ 527 .223 Varmint HB 1/9 twist in
2007. I could not get any good group shots @ 100 yards from when it was new.

On a hunch, I changed the firing pin spring that
I bought from J & P Products and now it shots
under 1" at 100 yards with most 50-69 grain bullets. The scope is a Zeiss Diavari FL in
4-16 x 50...

OahuKaneohe, how complicated is it to swap out the firing pin springs? I am also looking at the action screw sets to get away from the slotted screws.

thanks rch

Real easy, there are directions in the owner's manual.

quote:

Originally posted by RCHOUSER:
Only thing I ever noticed about Varget is that it tends to heat up my barrel quickly.

Somebody said one time that RL-15 would match the loads but run a cooler barrel. The next guy then said "yeh, but the RL's are heat sensitive".

From what I previously knew and now also checked:

R-15 is a double base powder i.e. it has nitrocellulose and nitroglycerin in it. Diisopentyl phthalate and Diphenylamine are also in it, and here they appear to be used as stabilizers.

Varget is a single base powder i.e. it only has nitrocellulose. It also has 2,4-dinitrotoluene in it which sounds exotic i.e. trinitrotoluene/TNT, but it isn't. From what I read, it is used as a burn rate modifier. It would appear that the energy is from good old nitrocellulose.

We all know that typically double base powders have more energy than single based powders, and often run hotter as a result. What is interesting is in this case, Reloader 15 has a heat potential of 3990 kJ/kg and Varget has a heat potential of 4050 kJ/kg. Varget is actually is the hotter burning of the two.

As a side note, 4050 kJ/kg is pretty warm for powder. For example Vihtavuori N540 is a double based high energy powder that is a barrel scorcher in .223 Rem for sure. Its heat potential is 4100 kJ/kg which isn't far off Varget.

I had always thought the R-15 would be the hotter burning of the two as it is double base. Well, clearly I was wrong on that...you learn something new every day.

As far as heat sensitivity goes, Varget may be slightly less sensitive from stuff from a few tests I read sometime back in 6mmBR.com or accurateshooter.com. However R-15 is the powder of choice in the M118 Special Ball Long Range .308 Win ammo i.e. sniper/designated marksman loads. Those rounds have to have well understood and predictable temperature sensitivity patterns. They wouldn't use R-15 if it were all over the map with temperature changes.

I have used a lot of Varget in .223, .308, and 6mmBR. I wonder if I would have saved barrels by using R-15 instead.

At any rate, with Varget you should get ~3,000 accurate rounds out of that barrel before groups start opening up. That is what I see out of mine.

50 years of reloading is a whole lot of experience handloading. I felt I have some experience at this point after 15 or so years. I am sure I could learn a lot from you though.

Webfeet, 50 years doesn't mean that I have an edge on you in success. It might mean I have more experience in what doesn't work. It definitely means that I am old....

All: I set up a series of loads from 24.3 - 25.4 gr with lapua brass, 205-M primers, and H-335. I had a significant tightening at 25.2gr Call it 3/4" with 2 touching and 1 flyer that pushed it out to .75 at 100. Still not what I call great, but, better than the 1" 3 shot groups that I have been getting. It blew back out to 1.25" at 25.4.

I am still not seeing any primer flattening, extractor marks, or any other pressure signs. I am loading to a coal of 2.257 which is .01 off the lands.

Question: Is anyone shooting a VMAX 60 in the 25.5gr to 26.0gr range? My Lyman 47 is showing 25.8gr as max. They may have been right all along.

I am going to set up 10 at the 25.2gr and run it over my Chrono to see where I am. I will also push a from 25.6 - 26.0 load series to see if the answer is "at the top". 26.0 is .2 over the Lyman Max.

Thanks to all that keep this forum great.

rch

It sounds like you are getting somewhere there.

If it were me, I would load up 15 or so at that 25.2 grain load that worked.

I assume that the 2.257" figure you gave was distance from ogive to lands, not full COAL. If that is the case I would try:

1 x 5 at factory COAL (2.260").
1 x 5 at 2.257" (0.01") off the lands.
1 x 5 at 2.247" (0.02") off the lands.

I am curious: are you using wind flags while you are shooting groups? I shoot on a windy range, and I don't shoot for groups without some sort of wind flag or flags. Even with a .600+ BC bullet at 3k fps, me missing a swirling wind there will just open up my otherwise nice tight group.

If I didn't bring flags, I hang up a piece of florescent orange surveyor tape on the 100 yard target frame. Then just watch for gusts before I squeeze off a round, and wait if it is gusting.

A 60 grain Vmax with a 0.265 BC at 3100 fps will drift 0.6" at 100 yards by a 5 mph wind at 90 degrees. That is easy enough to explain the group opening up if there was wind that day.

If you are seeing two bullets touching, you are at most 0.224" center to center or 0.448" overall. If a third taking it out to 0.75" (either c/c or overall), that is a ~50% increase in group size, and a pretty big jump.

I would be thinking wind as a possible cause, or perhaps a swing swivel stud catching on the front or rear bag.

Try shooting that load with tweaks, and with more rounds in your groups as they will tell you more. If the groups feel good (i.e. I didn't pull a shot), and the groups look well rounded, but larger than I expect, I look at the load. If the groups are tight and rounded except for a single flier or two (that doesn't feel like it was me pulling the shots), I look at wind, something off in the bag setup, something off in my hold, and then finally perhaps something in the gun/scope setup itself.

Last thought: those 205M Federal primers have soft cups. If there was a problem with a weak firing pin, it would be less likely to show up with Federal primer than say a CCI, a Remington, or a Winchester primer. In a hard to soft cup hardness rating, I would give Rem 7 1/2 tops, then CCI BR4, Win SR, and finally Federal 205M.

Having a soft cup doesn't rule that firing pin issue, but it would be less likely IMHO. Breaking out your Chrony will give you a better idea on an ignition issue via Extreme Spread and Standard Deviation on velocity. If you have ignition problems, you almost for sure will see inconsistency there.

Quickload has the following for 25.8 of H-335 and a 60 grain Vmax at 2.260" COAL (in a .223 Rem with 24" barrel):

Pmax: 67,678 psi
Muzzle Velocity 3330 fps
Case Fill: 102.1%
Amount of Propellant Burnt: 99.74%

Quickload may have it wrong. However if your Chrony has velocities of 3,300 instead of 3,200, I am pretty sure those loads are over pressure. The pressure for 3,220 fp/s would be around 59,611 psi, and a pressure of 62,177 psi would produce around 3,257 fp/s.

webfeet, thanks for all the help. Below are some more answers set up to try to keep them straight in my own head.

1. I agree. It's time to break out the chronograph.

2. I agree that the FEDS have a soft cup. I believe these will show cratering and flattening a little sooner. May just be another old guy's tale. I do have plenty of BR-4's.

3. I did not use my comparator, the 2.256 is coal (not ogive).

4> I have unlimited access to 100 yard fully climate controlled indoor range. T-benches, adjustable stools, and 100 yard remote cameras to an led screen at the shooting station. This kind of eliminates any alibies for wind etc.

Thanks for the quick load look. That is software that I have considered many times. I just can't quite pull the trigger. Maybe its time.

Again, thanks for all your help with this.

v/r rch

Not a problem. Let me know how the next attempt works for you.

From my notes and doing a little division, the best accuracy with H-335 in .223 is around 97% of max. You might try the Varget that we talked about as well if you feel like it.

If none of that works, then it is time to look for even contact with the factory bedding compound on the recoil lug, consistent action screw torque (35 inch # across both screws, and scope mount (not scope ring) torque (65 inch pound with the CZ factory mounts).

I figure you are loading with Lapua brass, you are loading with decent dies too so I will leave that out. I also figure you checked your scope on something else eliminated as a possible issue source.

You might mike (mic or mike?) your bullets and see if there is some weirdness in that particular box. I have seen 0.00075" difference in diameter in boxes of Nosler Ballistic Tips before.

If you are close to the lands, checking the ogive is consistent is a good thing to do. That is why I was suggesting moving back to a 0.02" jump. If there was a variation giving it that bit more room before the lands should help.

I measure at the ogive with my match and benchrest bullets, and I see differences. I assume it is depending on which machine produced the bullet at the factory. I see this with Sierra Matchkings for sure, and segregate the bullets by the variation.

If you are a benchrest or a high power target shooter than you likely know all this stuff already or are familiar with it...please excuse being "told" stuff you already know.

Increasingly, CFE 223 is my go to powder for .223

Most of my use has been with 69 SMKs and 63 SGK, but it is a sub MOA powder for 50 and 55 gr bullets as well (for me at least)

You may want to pick up a pound to play with before the election.

Duckear -

I haven't tried CFE 223 yet. Quickload has some impressive velocities with it in other calibers I reload. So far I have held back as I wasn't sure how well it would shoot.

Some of the other high performance, higher velocity powders that came out in the past few years haven't worked for me. The speed was there, but the accuracy was not. The one exception to that has been Reloader 17, which has had velocity *and* accuracy. That's just an off-topic side note though.

Thanks for the heads up on CFE 223, I'll pick up a can and give it a try.

I finally got to the range yesterday and none of the H335 - VMAX 60gr loads I made produced anything that I was looking for. I will now change powders and start with the 60 MAX again. I think RL-15 or Varget.

I was working on a parallel course Barnes 55gr bullet and the H335 since it was in the hopper of my measure. I now have a very nice load using a 55gr Barnes HP FB bullet and 26.5gr H335. I used the Fed match SR primers and COAL at 2.260. I was bumping along a set of loads between 24.5 and 27.0gr using .5 grain increases. The 26.5gr load showed up with really pretty .5" group (edge to edge) at the 100 yard mark. The 27.0gr group expanded again so I will work the 26.5gr.

Plan to load another series with the Barnes 55gr at 26.3, 26.5, and 26.7. I want to check to see if there is a sweeter node. I will need to chrono these load as well.

I have now officially ruled out using H335 with the 60gr VMAX in MY CZ-527.

thanks to all that make this forum great.

rch

How did you arrive at 2.260" for the barnes? If that's not the limit of the magazine, you might have more luck with adjusting that vs small changes in the powder weight.

Good luck, and thanks for sharing your results!

That is a great result with the Barnes 55 grain bullets and 26.5 of H-335. It is great you found something that excludes the rifle/action as being an issue.

Interestingly for me, your tight 26.5 grain load is 98% of your opened up 27.0 grain loads. That is close to my experience with H-335 loads around 97% of max being the highest velocity, accuracy node.

I added the Varget Quickload projections earlier in thread. I ran Reloader 15 as well since you thinking about trying it.

These are the R-15 projections for a 60 grain Vmax at 2.260" COL in a 24" barrel.

26.5 grains R-15 65,032 psi 3,303 fps (Over .223 Rem 62,366psi Pmax!)
26.0 grains R-15 59,598 psi 3,238 fps
25.5 grains R-15 55,507 psi 3,172 fps
25.0 grains R-15 51,724 psi 3,106 fps
24.5 grains R-15 48,201 psi 3,040 fps

Good luck with Varget and Reloader 15, and keep us posted.

23gr of benchmark was the load that worked best with my 527 Kevlar varmint and 60gr Vmax bullets

Came back to this to report the r-15 did it. It gives me what I am looking for. 24.5 gr + small match primer + Lapua brass at .226 col gives me .4 in edge to edge 5 shot groups at 100. I think this is going to be a little slow, but, I LOVE the accuracy.

v/r rch

[QUOTE]Originally posted by RCHOUSER:
Came back to this to report the r-15 did gives me what I am looking for. 24.5 gr + small match primer + Lapua brass at .226 col gives me .4 in edge to edge 5 shot groups at 100. I think this is going to be a little slow, but, I LOVE the accuracy.

v/r rch[/QUOTEThat's just great. roger