Dot Flip

[user293]

Im brand new to open this year, and ive been messing with a ton of different loads to try and get my gun to shoot flatter. i dont care about recoil, i just dont want the dang dot to leave the glass. every load i try, the dot leaves the glass, and seems to bounce too much. ive tried 3n38 (probably the best, but too hard to find around here), N350 with 124/115, longshot with 124's, 3n37 with 115/124, N105 with 115/124, AA7 jams my gun. all loads leave the glass when i shoot. i have a scheumann Hybrid with 3 ports, and a 3 port comp, thats pretty large ports. should i start messing with the recoil spring? i think my grip is good. what should i do next? heres a vid of me shooting it, and it doesnt look like much flip at all, but the dot leaves the glass non the less. thanks.

[BlueOvalBruin]

Hmm, I’ve seen similar issues with a friend’s gun with 3 hybrid ports in 38 SC. His gun made major but was flippy and the dot left the lens. I don’t remember the powder, I think it was HS6 though. He never resolved the issue (is currently putting in a 9mm barrel) but we were thinking that it needed more gas. I have another friend who uses 3n38 with his 3 or 4 port SVI IMM and his gun is flat as heck. I don’t know his load but it definitely uses a lot of powder.

[user293]

yea ive though about heating up a slow powder up to 175 PF but with half the powders i have, that may be danger zone, especially with 115's. thats like 9.2 GR of N350. pretty hot but it IS super comp case after all. i hope i can get my hands on 3n38 soon. need to try with 115's. only had 124's and a half pound to use when i bought the gun.

[Jman]

Not being simplistic with this suggestion. Stop dot watching. Let it go. Focus completely on your target.

Jim

[driver8M3]

i hope i can get my hands on 3n38 soon. need to try with 115's. only had 124's and a half pound to use when i bought the gun.

if you're near maryland...

http://www.brianenos.com/forums/index.php?showtopic=130373

[user293]

Not being simplistic with this suggestion. Stop dot watching. Let it go. Focus completely on your target.

Jim

i do let it go during a match. i dont worry about it. this is all at my house, focusing on the dot flip, after making a load, or shooting through the chrono. at a match i dont give a rip and just run. but i play with it to make it better at the reloading bench.

[robot]

heres a vid of me shooting it, and it doesnt look like much flip at all, but the dot leaves the glass non the less. thanks.

it looks flat to me.. more importantly, does the dot return to where it was fast enough for you? if it does, then leaving the glass isn't that big a problem.

[Jman]

Not being simplistic with this suggestion. Stop dot watching. Let it go. Focus completely on your target.

Jim

i do let it go during a match. i dont worry about it. this is all at my house, focusing on the dot flip, after making a load, or shooting through the chrono. at a match i dont give a rip and just run. but i play with it to make it better at the reloading bench.

I have not found any combination in major where the dot is real "quite". Rule of thumb of course, more powder = more gas = less flip. My Open G17 likes HS-6. STOUT recoil but little flip. Don't see much HS-6 used in 2011 type guns but is works.

[Chris iliff]

Play with your recoil spring. Try a pound or two less. After getting comments that my gun looked flippy, I adjusted WH pressure (more) and did drills with 10, 9, and 8 pound recoil springs. I settled on the 8, but it was a close call between it and the 9.

[Mitch Harrington]

I was having a similar problem and changed comps. The one I had was something Smoking Hole put on the gun when they built it and it just wasn't very efficient. I put a Bedell 7-port comp on it and it flattened out TREMENDOUSLY! A three port comp isn't much to help keep the muzzle down.

Edited June 14, 2011 by Mitch Harrington

[gng4life]

The video looks pretty good but like the previous post said, does the dot return to where you before you broke the shot? Playing with the loads is critical with each comp. I did a bunch of N350, PP, WAC, and HS6 over the past few weeks and I could tell a remarkable difference between WAC and HS6 at the same PF. I'm working on loads but with the HS6, I really saw a difference in the way the dot jumped in view.

I would also look at your recoil springs. I went to a 10lb for my 9Major loads and a 6lb for my 9mm Steel loads and it does make a HUGE difference.

Otherwise, you look good, keep up the work..

[Toolguy]

So which one was better - HS6 or WAC?

[BlueOvalBruin]

Having the dot just return to the same spot is definitely important, but having a gun that shoots flat is definitely better IMO. You've probably spent a lot of money on that gun, I would definitely keep experimenting with powders and springs to get it flatter. SVI recommends 3n38 for that kind of setup so try that again and keep bumping it till it shoots how you want it (while using a chrono and watching for pressure signs of course). Yeah it's expensive and not easy to find but you're shooting open.

[gng4life]

So which one was better - HS6 or WAC?

Sorry, I didn't make it clear - HS6 was much better. WAC seemed "violent" to me and the dot jumped straight up off the screen but returned to the same spot. WAC was great to reload, lots of room left but not enough to double charge and it metered very well. HS6 was really dirty, left some weird discoloring around my popples and really gunked up the internals but I need to run it to a higher PF to see if it will burn a little cleaner. The dot stayed in the screen just touching the top of the C-more but returning to center nicely.

It's a 5" Trubor topend ( I got from Eric "Aircooled6racer" here on the forums) with a 10lb spring.

[Pat Miles]

As stated above, don't hesitate to try different weight recoil springs. Also try different weight mainsprings. The combination of the two play a big role in recoil as well as dot dip when the slide closes. When doing your trials with the springs shoot timing drills and see if your group size shrinks or grows. Try ten rounds with each drill. This will tell you what spring combination the gun likes. It will take some time and effort.

Pat

[Kriojas]

All I have shot is open and I have tried many diffrent loads. I use a trubore comp with one popple hole. I use 10.5 of N105 with a 125gr zero bullet. This is one of the flatest loads I have used. 9.6 of 3N38 works good as well. Both of those loads hit hard in your palm but the dot stays flat.

[snake32]

im shooting a 3 port comp no holes in 38sc. 10.5 gr n105 124gr mg cmj with a 174pf. dot doesnt leave the glass. 9lb recoil spring. im not an expert but i have heard that popple holes require more gas so more powder to reach the same pf as without the holes. keep playing.

[user293]

heres a vid of me shooting it, and it doesnt look like much flip at all, but the dot leaves the glass non the less. thanks.

it looks flat to me.. more importantly, does the dot return to where it was fast enough for you? if it does, then leaving the glass isn't that big a problem.

Yea the dot return is super great, no problems with that. Just would like it a little less flippy. The 3 ports are pretty big so the comp should be fine at putting out gas

Edited June 15, 2011 by user293

[shooterbenedetto]

do yourself a favor and buy a 90 degree side mount. now you have solved ejection problems!

who cares if it looks funny, that was my first impression but after shooting it, it improved my

shooting( faster dot aquisition coz scope is soo low). Gun works 100%!! and buy adding a steel or aluminum grip on my 2011 it flattened even more!

I wish I had a video side by side when i bought it to the range. Had my buddies shoot 2011 palstic grip

with regular allchin mount then shoot the aluminum grip 2011 with the side mount...it was night and day

difference!! I believe it has something to do with the frequency of the metal during recoil(learned it in archery

making arrows and choosing different shafts to match our metal riser) and both guns were in 9major! what more if it was 38 super!

Also read in IPSC global Village that Double Alpha Saul Kirsh makes a grip kit that lessens about 20% in recoil also..

Edited June 15, 2011 by shooterbenedetto

[user293]

do yourself a favor and buy a 90 degree side mount. now you have solved ejection problems!

who cares if it looks funny, that was my first impression but after shooting it, it improved my

shooting( faster dot aquisition coz scope is soo low). Gun works 100%!! and buy adding a steel or aluminum grip on my 2011 it flattened even more!

I wish I had a video side by side when i bought it to the range. Had my buddies shoot 2011 palstic grip

with regular allchin mount then shoot the aluminum grip 2011 with the side mount...it was night and day

difference!! I believe it has something to do with the frequency of the metal during recoil(learned it in archery

making arrows and choosing different shafts to match our metal riser) and both guns were in 9major! what more if it was 38 super!

Also read in IPSC global Village that Double Alpha Saul Kirsh makes a grip kit that lessens about 20% in recoil also..

dont need a 90 degree mount as i dont shoot 9 major and i dont have any ejection issues whatsoever. the grip though that you talk about is interesting...

[Aircooled6racer]

Hello: When is the dot leaving the lens when the slide is coming back or when the slide goes forward? It does look like it is shooting flat. Is the dot going straight up and down or is it doing a figure 8 /question mark dance? I shoot into the burm to check the dot movement with no targets. I look at the dot to see what it is doing. Once I can see what it is doing I then change one thing and see if that corrects it. Let us know what you find out. Thanks, Eric

[user293]

Hello: When is the dot leaving the lens when the slide is coming back or when the slide goes forward? It does look like it is shooting flat. Is the dot going straight up and down or is it doing a figure 8 /question mark dance? I shoot into the burm to check the dot movement with no targets. I look at the dot to see what it is doing. Once I can see what it is doing I then change one thing and see if that corrects it. Let us know what you find out. Thanks, Eric

its going straight up and down when the slide is coming back. leaves the top of the lens. during the match tonight (and other matches) i notice the dot doesnt move as much as when im actually paying attention to (like at chrono at home, or just at a tree). sometimes ill take a new powder and just shoot it at a tree with no target/chrono just to pay attenion to dot movement. every powder feels nice but flips out the lens. im pretty much dedicated to 115 GR. bullets so i can get the most amount of gas possible. 9.0 Gr. of n350 is what i used at the match, and it was pretty good. i got a load of 9.3 Gr of 3n37 that is decent as well. also some longshot but cant find data for 115's and longshot, may be a pressure issue. ive shot a couple other fellow open shooter's guns in the past, and theres were terrific. big bang, tiny dot movement. not as good as mine. but i have not messed with springs yet, just bullet/powder combo. i think im gonna order me up some 3n38 since i cant get it locally, and its spendy here when its in stock. the gun liked that the most.

Edited June 15, 2011 by user293

[soaringf22]

i had a shorty that had the same problem all the powders from 165-179pf nothing worked well they all left the glass. i added tungsten guide rod and a tungsten plug, 9lb commander spring with a shok buff. after that everything stayed in the glass and i picked WAC as my powder casue it was the cleanest and most consistant up and down dot bounce. now this did make the gun heavy about 43oz but if you felt my limited gun, i like em heavy.

[Aircooled6racer]

Hello: I like the 115's also but in 9mm. I would get some recoil springs in the 8-11lb range and try them. I use ISMI springs from Shooters Connection. I would also get some mainsprings 15,17 and 19lb ISMI. Lastly check the radius on the firing pin stop. A firing pin stop with a good sized radius works well like the STI or Caspian. You may also try upping your powder charge some. On the shorty I had that actually reduced muzzle flip and it shot softer Thanks, Eric

[mtheaded]

I think its important to separate concept of rhythm vs recoil, although they are related.

Recoil per se if not controlled causes flip and excess dot movement.

Rhythm is how the gun feels and manifested by dot movement patterns, such as dot dipping or other instability, and speed of dot recovery to zero.

Rhythm is controlled by the interaction of the shooter and the gun. The usual suspects in bad rhythm, exemplified by dot dip, are mismatch of powder to gun (as in excess gas or powder that burns too slowly), comps, slide too heavy or spring too heavy, or bad grip.

Flip can be mitigated by some of same factors as rhythm, but getting back to OP’s question, what can you do besides powder to reduce flip? Two easiest things are to increase grip strength and recoil management with a thumbrest. In my experience, the thumb rest works the best. That will decrease flip dramatically to virtually no movement.

A properly tuned gun will not have dot leave center of scope and will be perfectly up and down which IMHO is best achieved with thumbrest.

And BTW 3 port comps work fine, I have tried many and settled on simple 3 port comp and dot hardly moves. Some great shooters like Jerry Barnhart and Chris Tilley have had excellent results with only 3 ports.