ballistics question

chiefks · 08-10-2006, 12:07 PM

I shoot a savage model 12 243 with accu trigger. It has a 26" barrel. Does the longer barrel help build any velocity for flatter shooting???

The other question is reguarding ammo. I shoot 95 grain winchester ballistic tips. The powder seems to burn better and the bullets don't seem to foul the barrel as much as say remington 100graincore loc's. Anyone have any ideas as to what the difference is in the ballistsics of the two? My gun seems to shoot flatter than the ballistic tables I've seen.

USMC PMI · 08-10-2006, 12:50 PM

Fouling can be different, companies use different types and brands of powders, even different bullets can foul more or less. The Win BSTs are molly coated, it is highly debated but many feel they foul less than say copper jacketed bullets.

The barrel legnth can help to a point but this is now a highly debated topic thanks to technoligy. Some of the newer powders used in SOME short action rounds can have the bullet up to speed in as short as 18". Experts debate that the shorter stouter barrels are effected less by harmonics and ultimately fire better long range and retain over 95% of the bullets speed compared to a longer barrel. I am not going for or against this theory, waiting for more proof and information. I would think that the .243 being a little smaller round than say the short action .308 win would benifit from the longer barrel as it will stabilize the bullet a little better. Many other rounds especially mags. (7mm mag, 300 win mag and the like) need the longer barrels to burn their huge, slightly slower burning powder charge completely.

hartshot101 · 08-10-2006, 02:47 PM

as myself id say that yes the longer barrel will give you a little bit added velocity but a 243 is primarily a small game and deer round. Win most ppl look to get a varmit gun they want a longer barrel for increased range and stability.

Secondly ive found that remington ammo does foul up your barrel a tad more than other brands. i primarily shoot winchester ammo in my 3006 and 308 for deer season and find that after a shot at the range or field that there is less powder and resedue to be cleaned. But here lately i have found that federal is the worse of the 3 ihave mentioned i always had to keep my 7mag clean after several shots. But again thats my opinion.

Ridge Runner · 08-10-2006, 03:21 PM

on average you should see around 35-55 fps gain per inch of barrel in a cartridge like the 243, win loads with ball powder and as long as the pressures are where they should be, it normaly burns cleaner than extruded (stick) powder. an added bonus is that ball powders are easier on the throats. The ballistic tip line for some reason has been longknown to drop less than it should, don't know why but run your actual trajectory through a ballistic program and find the actual BC by bullet drop and you can then reliably work up some drop charts. the CTBST's are not moly coated its a win patented substance called luballoy, have no idea what it is made of.
RR

cherokee_outfitters · 08-10-2006, 07:09 PM

Ridge Runner is correct, you will gain the difference 35-55 fps per inch of barrel in the 243 depending on the load. But atleast the 35fps for sure. Shorter barrels do not fire the bullet the same speed as the longer barrel. The smaller the caliber the faster you gain speed per inch the bigger the caliber the slower you gain speed per inch. This I've tested and know it to be a fact even in pistols.

Your second ? You need to know the speed of your bullet to compare it to the ballistics chart. Also if you live above sea level and depending at what elevation you bullet will lose less elevation drop due to air density. At 7500 ft this starts to really effect the drop and at 10,000 you just turned your regular 30-06 into a magnum class of ballistics at longer ranges.

Fouling may be caused by a softer jacker from the core-lokts.

chiefks · 08-11-2006, 10:07 AM

Well this has been a helping post for me. I don't have a chrono to check bullet speeds with. I just know my rifle shoots quite a bit flatter than the ballistic charts I've looked at. I've just been trying to figure out why, and came to the conclusion that it was several things working well togather. I'm in kansas, don't know what the evelation is, but its not any where close to high altutiude.Thank you for your help guys.