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Pilgrim
06-02-2006, 01:05 PM
I've been trying to get a load worked up for the double rifle lately. Trust me, they can be frustrating.

The first problem I'm dealing with is holding the rifle consistently. With my hard kickers, I've learned to hold them firmly to reduce felt recoil. With my double rifle, that technique causes the bullets to cross at 100 yds. Just by altering the hold, I can cause the bullet impact to shift by as much as 8" @ 100 yds. Nuts...lots to learn/relearn with this rifle, including how to hold this rifle consistently. When I do my part, it's a real shooter, last time out shooting factory ammo, it consistently grouped both barrels into an inch or less (same group for both barrels) at 100 yds. That is unusual to say the least for a double rifle. Anyway...I've almost got my loads worked out and yesterday head on out to the range to verify they group one last time before I load up a bunch of 'em. Here is where things went weird on me. The last time out to the range, same components, etc., the weather was in the low 70's. Velocities with the H4831SC and the Nosler 286 gr were about 2230 fps using a CCI 200 to light it off. Since the case is a real long one (imagine a stretched 30-40, necked up to 35+) I thought a magnum primer might help load consistency, so I loaded up a few with CCI 250's and yesterday headed off to the "proving grounds". Temp yesterday was in the mid-80's. Everybody KNOWS that higher temperatures will result in higher pressures and higher velocities. Right???? Nope. The same loads with the CCI 200 that chronographed 2230 last week chronographed 2130 to 2150 this week. The loads over the CCI 250 all chronographed at 2260 or so. Go figure. I'm going to try a heavier crimp and magnum primers for the next go around. The velocities have to be about 2230 for the barrels to regulate, so...back to the loading room.

The next thing that I thought might be of interest involved my 1886 Extra Light (.45-70). I've been (slowly) working up loads for this rifle using the RCBS 45-405 and 45-325. The 45 - 405 casts right at 425 gr ready to load, while the 45 - 325 casts at about 340 ready to load (WW + 2%). The 45 - 405 2ill be my serious work load and reaching 1900 to 2000 fps is no problem with 4895 or 2015 powders. Recoil of those loads in a 7 # rifle is pretty fierce, so depending on how tired I am and how late in the shooting session it is, groups suffer consideable. I've gotten groups around 1.5" to as much as 3" with the same loads at 50 yards. More work to do with the heavy load for sure. The light load uses the 45 - 325. I've been experimenting with both surplus 4759 and XMP 5744 powders under this bullet. I've noticed that the bullet (ACWW + 2%) lubed with LBT blue is giving me light leading wash at the muzzle when velocities exceed around 1500 fps. Since I've shot the heavy test loads after this, perhaps that also is impacting group size with those. Anyway, back to my story...With 25 gr. of 4759, the case looked very empty, so I decided to try the same load with no filler, kapok (1.1 gr.) and dacron (0.9 gr.) to see what difference there might be in velocity and accuracy. Here is what I found (5 shot groups @ 50 yds)...

No filler; V = 1448 fps, Sd = 23 // 4 in ~ 1" with one flyer out about 2"

Kapok ; V = 1517 fps, Sd = 12 // 4 in ~ 1.5" with one flyer out ~ 3", the group was "vertical" so I suspect it was me since the velocities were so consistent. I'm going to retest this one, but with 23 and 24 gr 4759 to lower the velocity into the 1400's.

Dacron ; V = 1502 fps, Sd = 6 // 4 in ~ 1/2" with one flyer out about 1.5" or so. This load will also be retested with 23, 24, and 25 gr 4759.

Why the fliers? I dunno, all of the shots felt about the same with the sight picture about the same. Perhaps I was getting tired as this testing was after the double rifle testing. FWIW...Pilgrim

Larry Gibson
06-02-2006, 02:30 PM
I've been trying to get a load worked up for the double rifle lately. Trust me, they can be frustrating.

The first problem I'm dealing with is holding the rifle consistently. With my hard kickers, I've learned to hold them firmly to reduce felt recoil. FWIW...Pilgrim

Are you shooting the double from a sitting position at a bench? If so I would suggest you change to a standing rest holding the rifle as when shooting in the field with a forearm rest. This was how the double rifle was shot at the factory when regulated. It is also how you will most likely shoot it in the field. Years a go i was working up some cast loads for a .450 and was frustrated as you are until I was informed to do the above.

Larry Gibson

StarMetal
06-02-2006, 02:38 PM
Larry,

You are most correct in standing and shooting the rifle off hand, BUT that only comes after you find a load that the rifle like, and that sir is where bench shooting comes into play. One shoot never sight any kind of rifle in on the bench and then not shoot it from a shooting position you may be using in the field because off hand shooting will more then likely be different then bench shooting.

Into old Joe's car analogy..you built a race car, then you put it on the dynamo. You learn alot from the dynamo, like horsepower, the hp curve, torque, and what little tuning tricks do..do they improve horsepower and torque, etc. BUT running on the dynamo and running on the track are two different things. I see this with benchrest and off hand out in the field shooting. I develop the load the rifle loves off the bench, then I shoot it off hand in various shooting positions I may acqure in the field and more then likely a good bench load shoots good off hand too. Just might have to readjust the sights for off hand shooting.

Joe

omgb
06-02-2006, 02:47 PM
What make of double is it? Curious minds want to know.

Pilgrim
06-02-2006, 04:05 PM
The rifle is a Chapuis UGEX in 9.3 X 74R. If you go to the William Larkin Moore web site you can see the exact rifle as it is the one I bought. They haven't changed the picture of that model as of yet. It is made in France, and that is the only gripe I have with it. I basically don't buy anything French made unless there really isn't another option. This model is "made for the masses" in Europe for driven game shooting and is essentially CNC made, with most of the fitting dealing with the fitup of the standing breech and wood to metal fit. Otherwise, it is mostly assembled from machined parts. If you are an expert in double rifles (I'm not) you can tell the difference from a "best rifle" and one of these from wood to metal fit and internal parts fitting, as well as balance. This is an entry level double rifle intended to compete with the spendier bolt rifles. There are a few makers of these rifles in Europe. Those I am aware of (entry level) are Chapuis, Merkel, Rizzini, and Zoli. I examined all of these at the SCI convention in Reno last Jan. I bought the Chapuis based upon how it fit me, balance, and makers reputation (very tough rifles). It was also a SXS while the others were O/U. I'm quite satisfied with this rifle, at least so far. I took it down to a double rifle gun smith in Oregon to work on the buttstock to better fit me, and to lighten up and smooth the triggers. The problem with gunsmiths, is there are probably no more than a dozen in the USA that are qualified to work on these rifles so getting them altered can be a problem unless you are within driving distance of the smith. This smith is about a 4 hour drive from me so that isn't too bad.

The comments re: shooting from a standing position and from a bench are both correct. The standing position is used with what is called a leaning stand, or leaning rest so that the rifle is supported as in a benchrest position, but allows the shooter to recoil with the rifle. This is primarily needed with the big boomers (.40 cal and up) so the shooter isn't beat up too much. The smaller cartridges are often shot off of the bench re: normal BR techniques. However, adjusting the sights is a fools errand until the loads are both shooting to a "single point" of impact (regulated). Mine pretty well shoots where you point it, so the sights (and scope) are not the issue. The issue is developing a load that produces 2230 +/- fps with very high uniformity. I thought I had the load sorted out with 65 gr. of H4831 SC and the 286 Nosler. I'm going to try a heavier crimp, magnum primer, and 64.5 of H4831 SC, and 58.5 gr of H4350, also with a magnum primer and the Nosler. These should work OK. We'll see. I will still need to practice holding the rifle so that I don't have the accuracy problem due to my shooting technique. After I have a FLGC load worked up and the barrels smoothed a bit more, I'll go to shooting the CB. Pilgrim

Larry Gibson
06-02-2006, 07:06 PM
Larry,

You are most correct in standing and shooting the rifle off hand, BUT that only comes after you find a load that the rifle like, and that sir is where bench shooting comes into play. One shoot never sight any kind of rifle in on the bench and then not shoot it from a shooting position you may be using in the field because off hand shooting will more then likely be different then bench shooting.

Joe

Got to disagree, With double rifles the load they like is the load the barrels were regulated to. The barrels had to be regulated so the impact of one barrel coincided with the other barrel at a specified range. That regulation was always done with a factory load, not a reload developed for that rifle. The rifles were fired from the standing position during the regulation process. With reloads for a double what you must do is find a load that replicates the ballistics and recoil of the factory load the rifle was regulated for. Therefore to get the barrels to regulate you must duplicate the same shooting process and use it during the load developement.

Larry Gibson

StarMetal
06-02-2006, 08:04 PM
Larry,

You are correct , but I don't think Pilgrem is going to contact the factory and find out what ammo and load they regulated the barrels with. He's either going to have to buy some factory ammo or reload his own to the same equivlant . He'll have to either find out how they shot it too. We're basically saying the same thing. We can pretty safetly guess the factory didn't shoot cast bullets, and Pilgrim said he's going to do that, so he will definately have to work that load up and I say it's alot easier off the bench to find a good shooting load then see how it shoots off hand.

Joe

Pilgrim
06-02-2006, 09:38 PM
Not to rain on your parade, but how do you figure I know that the velocity of the load for which the rifle is regulated is 2230 fps? Hmmm? Of course I shot factory ammo. That is how I know that the rifle is accurate and how I know what the baseline is for finding a handload for it.

I've shot over a hundred rounds of factory ammo so far. I use that ammo to make sure any changes I've made to the rifle haven't altered its' regulation. FWIW, the rifle was regulated with Sellior & Belloit 286 gr SP at 80 meters. A target is nearly always shipped with a double rifle, and it has the ammo info on the target. The rifle was also shipped with a certified copy of the proof test.

Cabelas had a closeout on the S&B 9.3 X 74R ammo a month or so ago. I couldn't afford to buy as much as I wanted, but I did buy 10 boxes of it. I paid $9.99 for the "on sale" ammunition and roughly $50/box for the special ordered ammo. At $2.50/shot, I don't plan on shooting a whole lot of factory ammunition. That plus the Nosler is a far superior bullet to that that is loaded in the S&B factory ammo. It (the Nosler) probably isn't needed at the velocities the 9.3 generates, but it is a comfort in any case. When I get around tuit, a cast bullet in the rifle should perform very nearly like a solid. Pilgrim