schmitz Posted February 24, 2004 Share Posted February 24, 2004 I've checked this forum and its topics but couldn't find an answer. Is there any scientific relationship between the dimensions of a comp ie it's holes and the gunpowder you use (esp. the burning rate of the powder) Please help me out. DVC, Henny Schmitz Quote Link to comment Share on other sites More sharing options...
ErikW Posted February 24, 2004 Share Posted February 24, 2004 Absolutely. What, you want me to quantify exactly what the relationships are? Sorry. Quote Link to comment Share on other sites More sharing options...
schmitz Posted February 24, 2004 Author Share Posted February 24, 2004 I'm busy preparing me and my gun for the Dutch Bianchi Championships. I own a SVI .38Super with a standard SVI 6-chamber straight ported comp. I developed a 6.4 N350 load under a 115 grain Fiocchi FMJ. This load works fine, but what I want to know is, can I improve compensation, using another powder, little bit slower/faster? What's the relationship between comp vs powder burning rate (not 2-stroke? ) HS Quote Link to comment Share on other sites More sharing options...
L9X25 Posted February 24, 2004 Share Posted February 24, 2004 Henny, You could try going to N-105 to see how that feels to you and if it is accurate in your gun. Modulating the powder speed can help or hurt you, depending on your comp port sizes and the current load you are using. The slower powder produces a larger volume of gas (good) but can decrease the operating pressure (bad) and the net result could be better or worse. You can get the same gun and projectile and pick a different velocity target and get different results entirely. Unfortunately, this will come come down to trial and error and what your preference is in *feel*. Leo Quote Link to comment Share on other sites More sharing options...
schmitz Posted February 24, 2004 Author Share Posted February 24, 2004 Thanks Leo for your reply, Somewhere on this forum somebody stated that Voigt uses N105 under a 115 grain bullet. I've checked my Vihta-manual but there's no N105 load listed under a 115FMJ. What load should I start with? PF should be appr. 145. Henny. Quote Link to comment Share on other sites More sharing options...
BrianH Posted February 24, 2004 Share Posted February 24, 2004 What do you mean by "compensation"? (Your definition) What are you aiming for? I mean, what are you shooting for? :P Are you going for "flatter" or "softer"? Different comp configurations do different things. Quote Link to comment Share on other sites More sharing options...
L9X25 Posted February 24, 2004 Share Posted February 24, 2004 Henny, I would start out at about 8.0 of N-105 and see how fast that goes. I know that it takes a bunch more to make major (well over 10grs) but I have no experience with powder puff 105 loads. To arrive at this load I compared the N-105 & N-350 weights to achieve the same velocity with similar bullets and used your current load to extrapolate. Good luck, Leo Quote Link to comment Share on other sites More sharing options...
SRT Driver Posted February 24, 2004 Share Posted February 24, 2004 Henny, WOW N105 and N350 in a Bianchi Gun!!!! That must be EVIL on the barricade!! I hope you have a light slide. I've used 4.3-4.4 of VV N320 to get 130 Pf with a 3 port comp. It is a really soft load. Makes my Open IPSC pistol feel like a a jack hammer. (but I've always wanted to shoot plates at 173PF. ) The trade off for using more comp and making the pistol flat with a slow powder might be more slap on your hand, noise and barricade vibration etc. It seems that the trend in the US was the opposite. Have you tried faster powders like N320 etc? Or is this a former IPSC Open Pistol that needs a juicer load to run? Good luck at the Dutch 'Cup. Quote Link to comment Share on other sites More sharing options...
SRT Driver Posted February 25, 2004 Share Posted February 25, 2004 Henny, Shred et al have a good thread that discusses this very issue "a Comp works By...". At least for a 'Cup pistol you can reach a point of diminishing returns, I feel. Quote Link to comment Share on other sites More sharing options...
schmitz Posted February 25, 2004 Author Share Posted February 25, 2004 SRT Driver, Indeed the gun I use, to shoot Bianchi is a former IPSC Open, The slide is lightened, a barricade mount is fitted, recoilspring is 9lbs and a Doug Koenig hammer fitted. Mainsping is 18lbs. With the 6.4 N350 load groups on 50 yards are within 4". Knocks down the plates well. Up to now I didn't use it on the barricades. I'm a little confused right now, I didn't try faster powders than N340. Maybe that's the way to go. Brian, actually I'm going for softer with less muzzle flip and I thought I could accomplish that by using slow burning powders (6-chamber comp). Thank you for all your replies. DVC, Henny. I'll check out the "Shred"-topic, thank you! Quote Link to comment Share on other sites More sharing options...
BrianH Posted February 25, 2004 Share Posted February 25, 2004 ....I'm going for softer with less muzzle flip and I thought I could accomplish that by using slow burning powders (6-chamber comp). I think you're on the right track, then. Quote Link to comment Share on other sites More sharing options...
.gif.53c483221c1b60d84bce93d42c5def5a.gif)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.