Testing the 30XCB

[Bjornb]

I have 35 rounds loaded with the NOE bullet and Superformance for shooting Sunday. 35 you say? Yeah was running short of cases. I may remedy that on Saturday. My loads so far are 48-49-50-51 grains. I also loaded a few with RL 19 in the 46-48 grain area where Btroj has been shooting. Finally a few cases packed full of WC867 to see what kind of speed I can get out of that powder. I have RL17 but I'm afraid that powder is on the fast/high pressure side. Finally I'm not done with H4831SC, will go higher there, and I also believe WW760 (H414) and LvR both have more to give.

Is there a particular reason why most of you guys are using Hornady-style gas checks? Are there inherent flaws with the Lyman gilding-metal checks? I'm just asking out of ignorance and would be thankful to hear your answers.

[geargnasher]

I'm using Hornady checks because I have a lot of experience with them and know what to expect. No other particular reason.

I did try some of a free sample 338remultramag's checks, they are nicely made but I never got much accuracy with them at high velocity. I had high hopes for them because when opened with a punch they fit the very tight .30 Sil check shank.

Gear

[runfiverun]

I believe the lymans are just re-packaged hornady's.
the only issue I got with them is I don't have any and can't get them around here.
I can pick up 30 cal hornady's at the LGS.

I have also used gator checks with good results on some h/V loads, they don't crimp on/in but are easier to apply to the base and stay put.
they squish to a flatter squarer base when I run the 223's into the swage die too.

[Bjornb]

Cool. I got a bag of 1000 in a mould trade so I'll be trying them. Thanks guys.

[btroj]

I am using Gator checks from Blammer. I bought 5 K or so a few years back and have a bunch left.
My understanding is that Run is correct, Lyman sells checks made by Hornady. I know Hornady makes bullets for ammunition other than their own. I am also pretty sure Winchester makes Hornady brass, I was told that n the past by a guy who's son worked there.

Gear, it gets worse with time. Know how your father complains about aches , pains, not being able to pee, and all that? Well, your next.

[Bjornb]

No, that's not how I describe seating/installing checks. What I described in post #239 was how I size, not how I install checks. There should be NO pushing the check on, the check should slip on the shank sitting flat against the bullet base. The check is then crimped on by the die during sizing being held against the bullet base by the punch. I accomplish this by sizing the checks with a properly made punch before installing them. After the checks are sized they are completely flat with none of the concave left and with slightly flared sides on the cup. I described this in detail to Brad and he plans on using his new toy to make proper check sizing punches.

If the check isn't perfectly installed perfectly flat against the bullet base and perfectly square to the bullet the best crown in the world is useless.

Any how, that's how I install checks and size the bullets in my quest for more accurate bullets. I fully believe the goals set out in this testing are 100% attainable, that's why I have been following these threads but little things will matter a lot and every little thing you can do to make a better bullet will pay off in the end. It's time to pick the fly poop out of the pepper barrel so to speak.

Rick

OK guys, please help me wrap my square Norwegian head around this gas check thing. I have no problem understanding how Rick (and others) seat their checks: use a punch to "open" the check slightly, then put it on the bullet shank and finally crimp it on with a Lee or Star die. What I DON'T get is how the Lyman 4500 gas check seater is INACCURATE. I took some pictures, and exaggerated the "before" pictures by purposely seating the check "cocked" before running it into the die (with the gas check seater installed).

This was a Lyman gas check, slip-on type (gilding metal)

....and a Hornady check (copper, crimp-on)

My untrained eye cannot see where there is a problem here. I have a small square and the gas checks are as square as they can be, I miked the rims all the way around and they are spot on. There are no concave or convex areas on the bases.

I'd appreciate any input.
Bjorn

[cbrick]

First, I've never used the Lyman 4500 gas check seater. Or the Lyman lubrisizer for that matter. Also I've never used the Lyman slip on checks and don't know how well they do or don't fit. I developed my method because forcing the check onto shanks they didn't fit on was shaving lead from the shank and seating the checks crooked. Worst were the SAECO molds but others weren't immune to it. If your checks are seating to your satisfaction completely flat and square I'd say you have no problem, if any of them do seat slightly crooked from a tight shank I think that would show up on the target.

Rick

[Bjornb]

Cool. Thanks Rick. It gives me something to work with. I just sent off a piece of 5/16 SS rod to Tim for turning down to a punch. I want to be able to do it both ways.

[detox]

Nose first works better for me because my press is slightly off center or not inline. I use the sizing stem to finish pushing bullet thru sizer. The matching 30 cal. bullet nose punch (hollow tip) will seat gas check more square around bullet base. I use the RCBS nose punch cut for the 165 Sil bullet, but the matching NOE version will work great also.

Gas checks do fit a little tight, but I have no problems seating without flaring. No flyers when target shooting

[geargnasher]

I actually did get to shoot tonight after work. Range was a balmy 70F, overcast, and ZERO wind, it's the calmest I've ever seen it there. Fall grass is in full seed, so there are "wind flags" from front berm all the way to the benches. Load was 44.5 grains of H-414 and enough buffer to sift in 3/32" above where the bullet base was to be seated. Brass was LC-69, second firing in this gun, primers were Federal 210, what I use for most everything that counts. Bullets were AM 31-190X, wd 50/50 aged five weeks, at 21 bhn. Hornady checks, put on base first while sizing .310 and lubing, then pushed through a .309 Lyman H-die with a press adapter (Lee-style). Lube was Felix, standard version, bore was scrubbed with solvent and a brush until completely clean, light residue of Ed's Red remaining, chamber dried. Bullets seated to just touch the lands at the very tip of the nose, otherwise they have a bit of a running start.

Groups were fired left to right, the first shot went high right in the left group. First five were culls based on neck thickness, felt both with the RCBS M-spud and when seating bullets in the customized Forster Benchrest die. They didn't shoot any worse than any of the other groups discounting the clean-bore flyer even though some of those cases will be tossed due to not holding the bullet firmly at all.

The final group, on the right, was a heartbreaker. First two shots went into the same hole dead-center. I SOOOO wanted to stop right there, but the remaining three rounds were "good" by my best estimation so I shot them as intended. Third shot went left, next one dropped low right, last one a tidge farther out to the left.

I'll say one thing, and it's not an excuse, but an observation. My bag technique stinks. I couldn't get comfortable, and the Teflon stock tape was binding in the bags, I guess due to humidity and leather. The first two groups were fired with my jacket on (yes, I wear a light mechanic's jacket any time it is below 75 degrees), the last two without the jacket and after spraying some silicone on the bags (no talc or graphite handy). This rifle is too light for free recoil and kicks too much to hold still, so I pulled it in hard to my shoulder and let it do it's thing, which after firing was jump way up and to the left, almost out of the front rest. I had to re-arrange everything after every shot and wiggle the rifle around quite a bit to relieve bind or preload forces. I think my trigger control is pretty good, I focus a lot on that, and didn't call any off shots. I could feel the rifle jump a little differently each time, though, as it bound slightly in the bags. Pulling back and forth to settle and check for binding spots before each trigger pull hopefully helped, but they shouldn't have been there in the first place. Next time I'll either lube the bags or hold the rifle with both hands and just use the bags for props.

I don't know how fast these were going, but without buffer on a hotter day this load chrono'd at 2540 fps and groups were more like 2-3".

Gear

[btroj]

My bench technique needs work too. I'm starting to get a better handle on it but I have work to do. My last trip out I was having trouble focusing on the bull. It would come and go from focus, I thought it was a problem with my glasses or contacts. Nope, it was mirage! Warm barrel and 45 degree air with no wind makes for horrendous mirage.

Ok Gear, you have me convinced. I will try some buffer next time out. I will try some RE19 first and see how it alters velocity before I try the 414 I just bought.

Were you suprised at all by the bad cases doing as well as the good ones? Any ideas on why?

[dtknowles]

I actually did get to shoot tonight after work. Range was a balmy 70F, overcast, and ZERO wind, it's the calmest I've ever seen it there. Fall grass is in full seed, so there are "wind flags" from front berm all the way to the benches. Load was 44.5 grains of H-414 and enough buffer to sift in 3/32" above where the bullet base was to be seated. Brass was LC-69, second firing in this gun, primers were Federal 210, what I use for most everything that counts. Bullets were AM 31-190X, wd 50/50 aged five weeks, at 21 bhn. Hornady checks, put on base first while sizing .310 and lubing, then pushed through a .309 Lyman H-die with a press adapter (Lee-style). Lube was Felix, standard version, bore was scrubbed with solvent and a brush until completely clean, light residue of Ed's Red remaining, chamber dried. Bullets seated to just touch the lands at the very tip of the nose, otherwise they have a bit of a running start.

Groups were fired left to right, the first shot went high right in the left group. First five were culls based on neck thickness, felt both with the RCBS M-spud and when seating bullets in the customized Forster Benchrest die. They didn't shoot any worse than any of the other groups discounting the clean-bore flyer even though some of those cases will be tossed due to not holding the bullet firmly at all.

The final group, on the right, was a heartbreaker. First two shots went into the same hole dead-center. I SOOOO wanted to stop right there, but the remaining three rounds were "good" by my best estimation so I shot them as intended. Third shot went left, next one dropped low right, last one a tidge farther out to the left.

I'll say one thing, and it's not an excuse, but an observation. My bag technique stinks. I couldn't get comfortable, and the Teflon stock tape was binding in the bags, I guess due to humidity and leather. The first two groups were fired with my jacket on (yes, I wear a light mechanic's jacket any time it is below 75 degrees), the last two without the jacket and after spraying some silicone on the bags (no talc or graphite handy). This rifle is too light for free recoil and kicks too much to hold still, so I pulled it in hard to my shoulder and let it do it's thing, which after firing was jump way up and to the left, almost out of the front rest. I had to re-arrange everything after every shot and wiggle the rifle around quite a bit to relieve bind or preload forces. I think my trigger control is pretty good, I focus a lot on that, and didn't call any off shots. I could feel the rifle jump a little differently each time, though, as it bound slightly in the bags. Pulling back and forth to settle and check for binding spots before each trigger pull hopefully helped, but they shouldn't have been there in the first place. Next time I'll either lube the bags or hold the rifle with both hands and just use the bags for props.

I don't know how fast these were going, but without buffer on a hotter day this load chrono'd at 2540 fps and groups were more like 2-3".

Gear

Now that's the ticket. Shooting small enough groups so that your bench technique starts to matter. Nice.

Tim

[cbrick]

Well, it will certainly be interesting to see where all this leads. Cast at 2500+ fps and groups like that and not happy. Hhmmm, I know guys that would wet their pants if they did that. I know that because I'm one of them.

I am by no means an expert on benching a rifle, not only have I never shot in a bench rest match I've never been to one. For they way I perceive your description of shooting position it's certainly different from the rifle shooting I've done from the bench. Hold the rifle still? I've never tried to do that & could use a better explanation. I try to make sure the fore end is in the front rest the same on each shot, same pressure on the shoulder and as consistent of one hand hold as possible much the same as I do with revolver grips.

Rick

[btroj]

My rifle is heavy enough to be manageable in free recoil. It comes back a bit but doesn't hurt, even with no recoil pad at all. Gear's rifle is much lighter and it would require more effort to control it in recoil.

I have been working on getting the rifle to recoil such that I can push it forward and it goes back to the proper aim point. No twisting, no sideways movement. It isn't always as easy as it sounds.

I don't know how difference bag technique makes but I gotta beleive it is at least 1/ to 1/2 inch in some cases.

[runfiverun]

sometimes I resort to an odd type of bench technique where I put both hands on the grip of the rifle [like a pistol]and use the left hand to pull straight back [and slightly downwards] into my shoulder.
I concentrate on feeling the trigger moving through the stroke with my right hand, and holding the cross hairs on a definitive point on the target.


if the rifle free recoils and jumps [bounces off the front rest actually] left or right the shot goes left or right too...

[Doc Highwall]

Gear, I have shot some groups like your last one and I found out what a I was doing wrong, the rear bag was not parallel to the front rest during rifle recoil. What looks like happened with your group is the rear bag was turned slightly to the left (looking down on it) causing the rear of the rifle to track to the right and pointing the muzzle to the left.


As a test try putting the rifle in the rest with it aimed at the target, and then deliberately turn the rear bag slightly left or right, then slowly pull the rifle back by the butt stock. If the bag is turned slightly counter clockwise the rifle points to the left, and if it is turned slightly clockwise the rifle points to the right.

[tomme boy]

Gear, you weren't too low behind the gun were you? My 308 hardly moves in the bags. When I am too low on the bench it seems to jump more in the bags. I do most if not all of my shooting off of bipods now. Learning to handle a gun on a bipod takes a lot of practice to get right.

The groups look pretty good to me for how fast you are going. Most hunters around here would kill for groups like those. Do you think the filler is protecting the base of the bullet and that is helping with the accuracy increase?

[geargnasher]

Thanks for the tips, all, I was really struggling tonight for some reason.

This stock has a round-bottom forend and with the Teflon tape, it just about won't sit up straight in the bags on it's own. When getting ready to break the shot, any tiny slight twisting pressure at all will flip the rifle. I even dry fired it a few times and it jerked a quarter inch or more off target just from the striker falling. It didn't jerk the same direction every time, and it wasn't my trigger finger or follow through doing it, either. My rear bag is a sand-filled Protektor with medium Cordura ears and it's packed hard. Front rest is the usual Caldwell base. The Teflon tape front and rear on the stock is very slick and lets the rifle slide and twist around with no effort, but if you bear down on it it gets twitchy and jerky. I can shoot better with a sporter rifle or lever gun held across my Nylon shooting bag. I think my problem is I was trying for a more free-recoil approach with the stock and rests, but it kicks too much for that, so I'm trying to hold it tight to my shoulder with my shooting hand and hold the rear bag with my off hand, but all that hard holding makes any movement under recoil between stock and bags very jerky.

Doc, as I fidgeted and fussed trying to get in position where the rifle would jump straight back (I'd slide the stock back and forth a bit to see where it wanted to go as I settled in to take each shot) I noticed the rear bag kept getting crooked. You are absolutely right, those ears have to be in line with the barrel and target or they'll steer the stock under recoil, I found that out many years ago but I had to fight it every single shot tonight, the way I was having to pull the gun in tight to my shoulder kept twisting the bag. This load kicks about like an eight-pound '06 shooting factory ammo, not the best for tiny groups to begin with, so I may have to re-think all the super-slippery tape and bags or give up and put a sled-type BR bipod on the front instead of using a solid rest.

Keep the ideas coming, guys, I'm like Rick, just never done the real BR thing before with rifles and even though I've watched a lot of utoob vids, done a lot of reading, and looked at a lot of BR gear, I really don't know how to hold this thing or set it up on the bench. It sure isn't like any of my other rifles.

Gear

[MBTcustom]

Gear, sounds to me like you would benefit greatly from a forend sled:
http://www.accurateshooter.com/gear-...rters-and-ars/

If your forend looks like this, you don't have near such a problem with your rifle rolling in the bags:
Attachment 119965

[geargnasher]

Brad and Tomme, the buffer is a wonderful band-aid. I was still a little surprised how it masked the wonky neck tension and thickness variations of the first five rounds (left group), they were bad. I think the buffer protects the base of the bullet and forms a solid plug behind it, which tends to push it more straight than hot gas pressure/burning powder grains do. I also think the buffer must be the great equalizer of neck tension and variable engraving pressure, it just insulates the bullet like a shock absorber from many of the inconsistencies in the things trying to move it forward.

Just a reminder, this bullet shot the WORST of any of the three I tried (the AM 31-185G and Miha .30 Sil were the other two), leading me to believe that the "Morse Taper Fit" was only good for the CBA guys at lower velocities. In fact, I never got the 190X to shoot really well above something like 2K fps, where the other two were holding an inch to 2400 and the .30 Sil was simply scary accurate at 2300-ish.

So I think there's something to be learned from the buffer here. Actually I know there is, which is why I won't even attempt to shoot cast in my Swedish Mausers without it.

Gear