Sounds like that would bring it back to about my 9,3x57 with a 24'' barrel ballistics
I bought a Model 640 in 9.3x62 with a barrel bulge under the front sight a couple of years ago. It keyholed bullets at 100 yards (well definately elongated holes in the paper) so I cut it at 20 inches and reset the sight. I got 2407 fps before and 2283 after with the Speer 270 grain bullet and IMR 4350 powder. A sample of one, but it was the same barrel, on the same day, before and after. Four shot average for each. It now shoots well-no keyholes but it is LOUD.
I have a 7x57 with an 18" barrel and it shot well with 4350 and N203, but I had no idea of what speed, bought a chronograph and tried some faster powders, 4895 and Win748. Now shoots 1.2moa at 2700fps out of an 18" barrel and no signs of pressure. I'd try some slower powders, you may be surprised what you can achieve with a little bit of playing around.
My 23.4" 9.3x57 runs 2,300fps at 10feet with 270 Speers. This load does not expand the web more than .0005" (1/2 thou) of a sized case. My 22" 9./3x62
Oberndorf Mauser runs over 2,600fps with the same bullet when using BLC2 powder, albeit the Speers are probably too soft for that speed. How much velocity is lost with shortening a barrel depends somewhat on the powder used.
I would personally use something like Varget or H4895 and would then expect a maximum of 30fps loss per inch.
A heavier, more appropriate bullet for the 9.3x62 would be the 286gr. Norma or Hornady and with that one, you should run about 2,350fps with the short 191/2" barrel. It will kick and it will bark with that load. H4895, Varget and BLC2 will all make this power level in the short barrel.
You could also use a 323gr. Norma at about 2,550fps - same powders. This is 100fps faster than the same bullet in my longer barreled 9.3x57.
Keep in mind, the 9.3x62 is a 78gr. capacity case (ie: IMP '06-type cased), while the 9.3x57 holds only around 57gr. capacity.
I am loading 286 gr privipartizans with 47 gr of 4064 in my 9,3x57's-with 23 and 24'' barrels-even though the case capacity is larger.Being totally new to reloading,I have a healthy respect for what overloading could do.This load seems pretty good,I don't know what velocity I'm getting, but there is no signs of pressure and it seems pretty accurate for what I reguire-moose hunting at ranges typically well under 250 yards-probably 50 to 100 yards would be more likely.I think 286 gr of soft lead would hit like the hammer of Thor at those ranges
But what I'd like to know is-if I get a 9,3x62with a 19 1/2'' barrel-will I basically be getting the same ballistics as my 9,3x57 with a 4'' longer barrel?Is there any real advantage to getting another rifle-other than the usual reasons for getting another rifle[It caught my fancy]
A ton of folks shoot CZ550 FS rifles with their 20" bbl and velocities run more like 100 fps less than a 24" does. Not that big a loss for such a reduction in length. Still a good deal better than a 9.3x57 at least at factory pressures.
I have 35 Whelens with both 19" bbl and 24" bbls. Sames load is less that 100 fps different in both rifles.
Exactly as z1r notes - efficient cases with moderate powders lose very little velocity per inch. My 22" 9.3x62 is running over 2,600fps with 270's so that means a drop in length to 19 1/2" in the same gun, should give me approximately 2,525fps, give or take a few fps.
rather be fishing, my 9.3x57 made 2,246fps with 48.0gr. H4895 and 2,300fps with 48.5gr. H4895. In neither load did the web of the case expand over sized diameter. It remained the same, which shows quite low pressure. The necks only expanded .001". My rifle has a large groove diameter and a long throat. I was using RP 8x57 brass. Since IMR4064 is a slightly slower burning powder than H4895, I'd be surprised if you are getting 2,200fps with your load= maybe only 2,150fps. Now, that load will kill moose all day long. I would not push it past about 200yards, though. You really need to chronograph your rifle.
thanks-I'll try some H4895-right now I'm using 286 gr Privi partizans and have some 270 gr''Swift'' bullets-which I assume should be moving a bit faster to expand properly than the soft nosed privi partizans.What weight bullets are you shooting in your 9,3x57 with that powder charge?
This is a copy-paste from the "Loading the 9.3x57" sticky at the top of this forum.
Well, the snow cleared enough to expose the benches and allowed me to set up the chronograph for some testing. It was an exciting day to say the least.
; 1st of all, sized ned brass measured .466" on the web - the largest size area of the 9.3x57 case. I was using re-formed 8x57, as noted elsewhere in this thread. Note that size - .466"
: I did shoot acouple groups at 100 meters, hand held on the bags, but has scope slip in the rings and groups were nothing to write home about - best group was with the swaged 300gr. RN's (.367") at 1.8" for 3 shots.
; Winchester Large Rifle Primers used in all loads. Previously, I'd done some pressure testing and came up with these loads to try. None of these loads were excessive in my rifle as shown by the expansion of the web. However, while my chamber is long, it isn't large ie: the Web area is perfectly sized for the brass. This is not normal for any American made rifle in which some examples show up to .008" expansion at the web due to oversized chambers. OAL means over-all-length.This chamber is overlong by .019", not oversize in diameter. Here are my chrongraph results:
: 232gr. Norma Vulcan - 48.5gr. H335 2.990" OAL - 2,317fps - no case expansion
: 232gr. Norma Vulcan - 50.0gr. H335 2.990" OAL - 2,362fps - no case expansion
: 232gr. Norma Vulcan - 54.0gr. BLC2 2.990" OAL - 2,336fps - no case expansion
: 232gr. Norma Vulcan - 50.0gr. H4895 2.865" OAL - 2,442fps - .4662-" ie: .0002" expansion in one spot only.
: 232gr. Norma Vulcan - 52.0gr. H4895 2,990" OAL - 2,436fps - .4662"- ie: .0002" expansion in one spot only.
:220gr. Horn. FN .375 to .367" - 52.0gr. H4895 - ?OAL- 2,547fps no expansion
: 225gr. Horn.SP .375 to .367" - 52.0gr. H4895 - ? OAL- 2,558fps no expansion
: 260gr. Speer cup pointed 270gr.-45.8gr. H335 - 3.045" OAL -2,188fps - no expansion
: 270gr. Speer SemiRN - 50.0gr. BLC2 - 3.045" OAL - 2,111fps - no expansion
: 270gr. Speer SemiRN - 48.0gr. H4895 - 3.045" OAL - 2,268fps - 1 case out of 10 showed 1 ten thousanth inch expansion ie: .46610 in one spot
: 300gr. Horn. RN- swaged to .367" - 45.0gr. H4895 - 3.070" OAL - 2,170fps. 2 case out of 10 showed .4662" and 1 case showed .4661" expansion ring measurements - in one spot only. The rest showed no expansion at all.
: Although I did not get even 1/2 thou expansion over sized brass with the top loads shown, I prefer to not go any further in this M46 Husky. As noted earlier, my chamber is a tight one. In previous testing without the chronograph, I did get expansion of .001" in earlier testing, ie: to .467" in some re-formed .30/06 brass, but it was slightly larger than the 8mm brass to start with. I feel my goals have been met for good useable ballistics for this round. It will make a great iron sigthed guide rifle and hunting rifle for that matter. Now to sight in the 'irons'. The scope is off.
; The ballistics speak for themselves and the best loads will be duplicated at a later date and retested. The temperture yesterday was 6C, which is about 43F or there abouts, along with a 15mph wind. As I noted, the scope was sliding foreward in the rings until it contacted the rear sight - didn't see that until finished - however did not a big POI shift at one point. Groups were not great, but OK for a hunting rifle, regardless of the scope movement during shooting. The 300gr. swaged .375's went into 1.8" and the 270's with the top load of 48.0gr. H4895 logged 1.9" and 2.0". I am sure I can do likewise with just the irons, given a suitable aiming point.
: Best load ballistics:
: 232gr. Norma @ 2,436 fps (long seat for accuracy)
: 270gr. Speer @ 2,268 fps
: 300gr. Horn. Swaged @ 2,170fps - I was absoutely floored with this. This load exceeds the original 9.3x62 factory load using a 286gr.soft and solid at 2,175fps. The load John Taylor was impressed with for all African game.
: All of these loads develop from 3,057fpe to 3,270fpe if that interests you.
: Reduce all loads by at least 5% before attempting to use this data in your rifle. Pay particular attention to cartridge overall length. Seating deeper raises pressure over long seating.
: My rifle has a .470" groove diameter, a full .004" oversize. This in itself is a pressure relief valve.
: Note the difference in velocity AND charge using H4895 with the 232gr. Norma Vulcans. The only difference in the loads is the overall length and charge. Not how the longer seating depth produced the same velocity even though the charge was increased 2 gr. This shows the longer seating actually reduced pressure, requiring an extra 2gr. to match precious velocity and pressure. With these larger calibres, more is gained by seating out and therefore increasing the case capacity, than seating deeply and making the leade into a freebore. Seating out is usually the most accurate of the two systems. In smaller calibres, these roles reverse.
: These ballistics are OK for about 99% of one's hunting needs. The lighter swaged 225gr. SP's at 2,560fps and the 232gr. Normas at 2,436fps make shooting deer out to 300yards an easy propostion is set 3" high at 100.
: The 270 and 300gr. make easy trajectories for any moose or elk to a good 250 yards - if the shooter is capable and practised for either, deer or larger game. The 232gr. Norma and swaged 225gr. Hornady make for good smaller big game loads to 300 yards. I am sure they would both do a credible job on moose and elk too.