What the difference? 20 VT and 20 SCC?

[300meter]

Can someone explain the difference between the 20 VT and 20 SCC? Can you post a picture? THANKS

 

[Phil]

The SCC has a 40* Ackley shoulder.....

 

[Wirelessguy2005]

As Phil noted the 40 degree shoulder is the most obvious difference. Additionally it has a little more capacity, much less case taper, more efficiency, and match grade reloading dies by Whidden Gunworks. Just to name a few differences. ;D

The 20 SCC will produce speeds of 4,000 +fps with great accuracy and no pressure signs, you won't find that with a 20 vt. During load development with 32 grain bullets i was generating 4,000 fps with fireform loads that were well under a 1/2". With formed cases i was generating 4,100 fps with 32 grain bullets and 1/4" groups. There is a ton of information about the 20 SCC over on SmallCaliberClub.com

 

[Wirelessguy2005]

Here are a couple pictures for reference. While the two cases don't look that different in the picture there is a night and day difference between the performance level.


The left cartridge is a standard Vartarg, the right case is the new 20 SCC cartridge

velocity while fireforming

 

[300meter]

That's a interesting cartridge! Appreciate all the info.

 

[SS427]

Night and day difference? I'm finding that a little hard to swallow. Can you provide more info as to why you think that?

 

[Wirelessguy2005]

otter,

The 20 Vt's that i have owned/tested typically generate about 3,700 fps on average. The 20 SCC will generate 4,100 plus while still maintaining great accuracy. A solid 400 fps gain is night and day to me in a small caliber, especially the 221 fb case.

 

[SS427]

That comes out to a 10% increase in performance with the 3700 fps figure you quote and a little less than 8% at 3800 fps. I probably load my 20 VT at 3600 fps.

How much and which powder are you using to hit the 4100 fps figure? Do you think it comes at the expense of accelerated barrel wear? I know there is rarely a free lunch when it comes to this stuff.

 

[Wirelessguy2005]

I agree there is rarely a free lunch when discussing speed, barrel life, case life, etc. I believe the 20 SCC is the perfect mix between the 20vt and the 204 ruger. In my rifle i use 21.5 - 21.7 grains of Accurate 2200 powder to generate 4,000 - 4,100 fps during the summer in the pdog fields. To date i have done this with no noticeable barrel wear or brass failures. I believe the barrel life of the 20 SCC will fall somewhere between the 20vt and the 204 ruger. However that depends somewhat on the quality of the barrel used and even more on how the owner cleans/maintains/treats the rifle.

 

[ab_bentley]

I hit 4250fps with the 20VT standard. 22gr AA2200, 34gr Dogtown Bullets, CCI450 primers, Rock Creek barrel, LC custom cases. I had over 10 firings on 50 cases with no loses, no extractor marks, no pressure. I'm not the only one who has got that too. How about 3900fps with a 40gr VMax, did that too, reloaded those cases over 10 times aswell. I had almost 3000 rds down the tube prior to selling it, it would still go .5" for 5 shots.

Adam

 

[L.Sherm]

4000fps is not the norm for a 20Vt. Adam what length of barrel and action were you using. I was a little disappointed at first with my 20 SCC when I first started chronoing it thought I was only getting 3850fps at first then found out my 25 year old chrono was about 150 fps slower than others. I was using aa2200 34gr v-nitemares in a 24 inch barrel in both. I'm not a fps guy but if you are I think the 20SCC is easier to reach that 4000fps. IMHO it boils down to personal preference some are fine with a 280 and some like the 280AI different strokes for different folks.

 

[Wirelessguy2005]

AB,

Those are some pretty impressive numbers from a 20 VT. I remember a guy that had really impressive numbers like that from a 20 PPC one time, i think he was getting 4,300 - 4,400 from it. If i remember the story correctly the barrel only lasted a few hundred rounds before it gave up the ghost.