Hi guys. I see nsa have both cup base and flat base. Does it matter which base for the best accuracy? I've seen other brand of slug have most cup base. I have a 600mm .25 cal slug A liner. Just want to know if u should go for the flat base or cup base slugs.
Cup base or flag base?
- Thread starter PigeonMan
- Start date
https://www.airgunnation.com/threads/flat-base-vs-dish-base-slugs.984887/
Check this thread out from previous discussion.
Check this thread out from previous discussion.
Upvote 0
It could be a way for you to control how far into the barrel the slug is pushed by the pellet probe? Slugs would probably be pushed into the barrel further than a skirted pellet.
Upvote 0
Only your gun could tell you which is the best .. my 4 uragan like cup base the best.. my 2 cricket compact like flat base better..that is why non are discontinued.. some like flat base..some don't..
Upvote 0
I've tried both in my Crown mk2 600mm barrel. The 29 gr. cup base seems to give the better accuracy but seems to likes between 950 to 970 ish fps velocity best.
Upvote 0
I’d also like to know more about the experiences of others using cup-base slugs over or compared to dish-base slugs. For those of you who have found cup-base slugs to perform more accurately, why do you think they are more accurate airgun slugs? Are there distance limitations to cup-base slugs?
Upvote 0
In most cases it’s about seating depth. If a guy has two of the exact same slugs, one flat base and one dish or cup. The dish shoot but the flat won’t. If he would put a .003 dimple in the flat base for his pin probe, the flat base will probably shoot as well as the dish. If you can’t adjust your seating depth with your probe or lathe with a reamer, you do it with the depth of the base of the slug.
Upvote 0
@Vetmx the differences in seating depths is not something I’d considered, but I have read some posts regarding the cup base being advantageous due the the flaring out of the base (similar to a pellet skirt). Now I can totally see the cup base flaring out occurring in black powder rifles. But I wonder, is the pressure from an air rifle substantial enough to flare out the cup base thus creating a better seal and contact with the rifling? If so, is the drag on the projectile affecting or limiting the effective range of a cup base projectile? I may not be connecting all of the factors properly, but I’m trying to gain a better understanding here.
Upvote 0
Some things or theories come from limited understanding. We question why something is happening and go with what makes the most sense based on our knowledge. But the more you know, the more factors suddenly appear. Then it’s not as simple as my gun needs the butt of the slug to flare out. If that’s the case, nobody should ever be able to shoot a boat tail slug. But they do. Think about it. In slug land there is a lot of misinformation.
Upvote 0
I have found that barrels will tell you what works as well as fps. My Hatsan Factor RC has a "sloppy "barrel . Only skirted or hollow base slugs shoot at a hot tune. Rifle brand 20 gr. have a hollow base and give great accuracy to 70 yrds . JSB Knockouts MK ll's do very well in my FlashPup . H&N 's do great in my Evinex AirSpeed . Experiment , hopefully your gun will pick one or so that works .
Upvote 0