Fussy Hornets

[murphy]

Have just completed a series of tests, with my Armi San Marco 22Hornet and made a few discoveries that may be of interest to the Hornet people. Firstly my rifle is a miniture Fraser falling block replica, it looks just like a Ruger #1 but the action is only half as big. It has a #3 profile 231/2" barrel half octagnal and half round. What I was trying to understand was why Hornet rifles can give top accuracy one day and poor accuracy the next, and have drawn a few conclusions. My conclusion is that quality control of handloads is the key, and that uneven seating depth is the single greatest destroyer of accuracy as the Hornet has a tiny and unforgiving accuracy window as compared to a 222Rem. or a 308. My tests showed me that a seating depth change of .010" can double group size, but as long as tolerences were kept to a minimum, accuracy was indeed repeatable. Another strange thing about my rifle is that it seems to have a false accuracy window as well as the true one. When bullets are seated .118" off the lands accuracy comes back to .3" for 3 shots at 50yds which is the same accuracy as .01 jam. When I tried 5 shot groups at 100yds, the one on jam shot .736" and the other seating depth shot 1.473". I thought it was an abberation so I tested a different bullet weight and the false accuracy window appeared just as before.If any body can explain or has experienced this, I would love to hear from them

 

[Montana Pete]

Don't mean to hurt your feelings or anything, but. . . .

Your rifle seems so incredibly touchy that 1/100 difference in seating depth means the difference between good and bad performance . . . .

It appears to have other neurotic "sensitivities" as well . . . . some hair-thin change or other in your loads that ruins your day at the range . . . .

I personally would just trade that one off and get a different rifle . . . .

 

[John Kielly]

I seem to recall from my old Hornet days that I could get close to .010 headspace variation depending on how I prepped the paper thin brass. The issue was that the technique was to cut the rim separately after chambering 40 odd years back & my rim had a certain amount of "noise", as the computer buffs say. Maybe you have similar tolerances with your chambering.

I can't recall it being all that much of an issue anyway when I made sure that I fully seated the case before lockup. That little Martini would shoot MOA or thereabouts & out to 150 yards or so, the foxes didn't seem to notice any performance issues with the little Sako pills or cast.

However, I suspect that with a non camming action like ours, ignition variations might result from casual, inconsistent case seating.

By the way, what primers are you using - rifle or pistol?

John

 

[murphy]

To all my friends at Benchrest central forums, Hornets certainly have their quirks but I suspect they apply to all Hornets and not just mine. If I wanted a less tempramental rifle I would go out and buy a 221 Fire ball. The challenge is in getting a rifle that looks like a toy and weighs 5 lbs, to shoot well, and with 5 shot groups around .73" at 100yds I pretty well have this ones measure. Tolerences are not a big problem if you know where the edge of the cliff is and go away from it and not towards it. My load uses Remington Peters brass with the rims filed down in a jig to give firm but not excessively tight head space, CCI 500 small pistol primers, 11g of W296 powder and either 40g nosler ballistic tip or 35g hornady projectiles. The Noslers like to just rest on the lands and the Hornadys need a small amount of resistence into the rifeling. My rifle has a Burris Fullfield 2 4.5 to 14 AO scope in Weaver mounts sitting on a couple of steel blocks fabricated by yours truly.

 

[Nader]

Oh boy, Here goes !
I'm shure I will be crucified for this response but try and understand my state of reality before you guys start driving nails.
The first thing you gotta get a grip on is that a Hornet is a 100-150 yd woodchuck or similar varmint type cartridge ,it was developed by Moses or some other old timer in pre-historic times.It was designed to shoot 45-50 gr round nose or spitzer bullets,That's It ! don't try and turn it into a .222, cause it will never be!
Case resizing is a delicate matter,cause the case walls are so tapered and thin,once you get a handle on this, it's rem 6-1/2s, not pistol primers! Followed by a case full of IMR 4227 topped off with an old style hornady,or rem or nosler 45gr spitzer seated to just touch the rifeling. 3/4 inch groups at 100 are the norm,but a Woodchuck is 4 times that size so no sense trying to refine a lump of coal.
Good news is( because of the mild report) that a woodchuck at 80yds will let you miss an offhand shot and he will stand there and let you reload and try again. No other centerfire chambering will cut you that kind of slack !
Have fun ,
Joel

 

[murphy]

To Joel

I can certainly see where you are coming from but none of the hornets I have owned, and there have been quite a few would shoot 3/4"groups with your kind of care and attention, and come to think of it, this is the only one I have owned that would shoot 3/4." This might sound a bit strange, but I get some sort of perverse satisfaction out of making a tricky rifle in a difficult caliber shoot well. The care and reloading principles I am using and discovering are universal and apply to all calibers and hopefully will make me a better shooter.

 

[brian roberts]

I'm wondering if the Hornet...........

given that sloping shoulder, would allow you to try sizing it, a' la Contender techniques to change the way it lies in the chamber. I'm wondering if it could contribute to the accuracy as a result???

 

[murphy]

Brass Reszing.

Don't know what the Contender boys get up to, but personaly I full length size all my hornet brass. I think that with grouping around .7" I have squeesed about all the accuracy potential out of this one that it is capable off. One day I would like to build a "super hornet" on a Zastava Mini Mauser action and a Dan Leija barrel.