#1
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Fastest 20BR / 20PPC
Hi im curious as to whats the upper limit of performance people have got from the larger .20 caliber rounds. Has anyone managed to exeed, say, 1600ft lbs with these rounds? Do they tend to prefer long barrels for this kind of performance?
And how does throat wear compare with the hot .22s? Thanks Last edited by rich; 09-18-2021 at 08:31 PM. |
#2
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Member L461 has had both chamberings, and chose to move the .20BR on and keep the .20ppc......
Marcus |
#3
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Quote:
I shoot the Berger 55's in my 20-250 at 3650 and it's a reasonable load, certainly not redline, but even at that speed I'm not expecting much life past 600 rounds. Last edited by B23; 09-18-2021 at 10:02 PM. |
#4
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Oh thanks. Is the barrel wear more due to velocity or is throat wear the main issue
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#5
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Generally the more overbore a cartridge is the more abusive it is to the throat.
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#6
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Yes, technically, in addition to the hot gases and particulate erosion from the burning powders, the quick repetitive hot/cold cycles cause thermal fatigue of the steel in the barrel, especially in the throat.
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#7
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As Branxhunter said I had both them
The 20 BR was built to use 50 grain Projies and the 20 PPC the 40`s I have acheived 4150 fps with the 40`s in the PPC but it was a hot load in the little Sako action.It shot really well with any projectile and powder combination. 32,35,40`Nosler,Hornady,Sierra or Berger.Basically the 6BR ease in a 20 Cal 4300fps with the BR case and 40`s this again was a hot load in the L579 action. I cannot remember the velocity for the 50`s http://www.saubier.com/forum/images/icons/icon9.gif While accurate the 20BR was on the ragged edge superb today not so in a weeks time it was hard to find the sweet spot and maintain it. If I dropped the load down to the PPC area it shot consistently. I sold the 20BR as it was just to frustrating The PPC is showing lots of fire cracking and throat erosion but will still put 3x40 gr Vmax into 3" at 500m not Target rifle accuracy but for somewhere over 2,000 rounds that is not surprising.
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Speed Kills |
#8
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I have both variants, the 20 Nitro ( 20BRAI) will easily do 3750 with the 55's in a 28" barrel ive never pushed it harder with the 55's because it shot so well there. 3G9 twist 3 shot group .078 in a Rem 700 boyds stock and 14oz trigger nothing special. I tested some of Badger Bob's 46 gainers at 4050fps in it also same thing never pushed it its were they shot the best.
My 20 Blitz (20PPCAI) will easily shoot a 39 gr.bullet at 3900fps as far as accuracy with both pick one. If I was wanting to shoot past 400-500 20 Nitro gets the nod with 55-s. If I was building one today I would see if Bartlein would make me a barrel with there new 400 steel in a 9 twist for the 20 Nitro or a 11 twist for the 20 Blitz. Define what range you wanna shoot and pick the one accordingly. |
#9
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Sorry for late reply. In terms of reducing throat wear, are there very cool proppelants available these days that are more ' barrel friendly'?
And what about advanced barrels, for example nitride treated barrels....thanks |
#10
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Regardless of the powder you use, which can and will heat the throat faster and hotter, remember the main reason a throat/barrel gets burnt out fast is due to firing to many round at one sitting and getting that barrel hot.
Heat/friction cause the most damage, the fastest. |
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