Hercules Bully owners- I may have solved the flex scope rail issue

Jaland, I not only got rid of the bottle cover with two barrel shrouds as part of it, I swapped out that 21” long, hollowed out scope rail to one of the Bullmaster which is a solid piece of aluminum and only 10 1/2” in over all length. If your trying to remove all flex from that scope rail, don’t just remove the bottle cover, switch out that scope rail also. The holes at the breech block attachment to the first barrel shroud band are exactly identical. It’s an easy, straight across bolt on. The bullmaster rail was inexpensive at $29. Made all the difference in my accuracy. 

That scope rail from the factory on the Bully is hollowed out and can easily bow. Just to prove my point, with out the bottle cover attached, and now you have all this rail just hanging out there, push down on it. You will see the flex downwards. 
 
I have tried several bullets and round balls. This gun is very powerful but because of the scope rail I can't tell anything about consistent accuracy. I have tried Hatsan's 168gr and a 196gr from Nielsen, and round balls. I bought this gun to use for the Texas whitetail season and it does register 225fpe with the 196gr hollow point. I love the look of the gun and I have an idea to fix it if I have to, but I have requested my money back and I am waiting to see what Hatsan has to say. I wish they would do a recall and re design the rail.
 
Jland, to answer your question directly, no, I do not have any movement t the second barrel shroud band, the one that’s still within the rifles main stock. If yours is like really loose, I am only assuming that there is some kind of fastener attachment that may have either come loose, or was loose from the factory. I have never had that much of my gun apart to see how that barrel band is physically attached. 

Just an FYI- when I sent back my rifle after a month of ownership back to hatsan in August of 2018, I, too was hoping for either a refund offer due to my gun being a lemon, or maybe hatsan re send me a brand spanking new one. Mine at that time could not even make it into my pellet trap set 40 yards away, and the size of my pellet trap is 10” x 10”. Something was terribly wrong with the gun to not even form a group inside of that trap, and the final straw was a rattle noise coming from somewhere inside the bottle area. 

Hatsan found that something within the valve system had worked its way off, and it was probably loose since the time I unboxed the gun. They assured me less than 1” groups were what they were getting at 45yards after the repair. 

After I got the gun back, I tested it, and yes, I was able to get at the tightest group about 3/4” at 40 yards. Rattle noise was gone. But I knew the gun could do better. I’m not going to rehash everything all over again, but the final fix was eliminating that scope rail. If I were you I would first email hatsan and describe what your barrel band is doing. They’ve been really good at getting back to me within 24 hours if not sooner. 

Lastly, have you tried reducing the velocities at all? Most guns shooting over 1000 FPS do not do well accuracy wise. Try backing off the hammer screw a bit. I dropped mine 12 whole turns counter clockwise so I am now at around 870 FPS, vs the 1072 that it was set at from the factory. Airgun Depot has made about three or four YouTube tutorials on this gun, and adjusting the hammer is one of them. Check them out.
 
I would love to be able to get a decent group at 40yds. There may be a way to tighten the second receiver mount, but I cannot see a way without disassembly. I can visibly see the movement in the second mount so I must go there next if I can't get a refund on the gun. I think Hatsan may be like Ford and unwilling to admit a problem with this gun because of having to fix them on a recall. Mine is shooting a 196 hp at 720fps which is just barely able to make the Texas qualifications. I like the look of the gun and if I could get decent accuracy out of it I would keep it.
 
To Barber and Jland- I would seriously consider changing out that scope rail to one off of the Bullmaster, or even the one off of the flashpup, and Jland, while your doing that, investigate that second shroud band. I looked thru the schematics of the Bully last night on Hatsan’s website, and see no fastener holding that down. It looks like an interference fit, or better yet a squeeze fit between the parts above the breech block. The BM scope rail is only $29. 

If Hatsan did do a recall on these Bully’s it’ll be accuracy related, not power related, and about the only thing I see them doing is making that factory rail in solid bar stock, and clip it shorter to around 18 1/4”, which would be just past the last shroud on the bottle cover. Just my honest opinion.

If you don’t plan on going the scope rail retrofit, try this- don’t ever use that pic rail under the bottle cover for bipod use. Instead, set the rifle on a rest, and place the rest directly under the main stock, not the bottle cover. I have a feeling your accuracy will improve in just doing that.
 
1542152100_6901165245beb5fa4f24221.07862436_87744B9C-DD5C-4EE3-A002-6272DAB34689.jpeg
1542152101_3288062795beb5fa55c0fb1.26677768_22C75E50-B998-4E7D-854B-CF3C214DBCAB.jpeg
1542152101_13888586495beb5fa5b929d4.27680158_38250389-9D42-4951-9D5B-DC3B991BC488.jpeg
UK bottle clamp,is in! Fits nice and tight. Here are close up pics of the quality of build. The maker also provided a 1/4 round cut out for guns with barrels really close to the bottle
 
1542152237_21373239405beb602d62b942.99644116_DF12DFF8-19F1-4747-8143-9EB87DC7A36A.jpeg
1542152237_21265740605beb602dc89fc0.35819969_EE3A5D90-E4FB-425A-B80D-9B9D53BC080F.jpeg
1542152238_21340791085beb602e34f4b4.41925835_9A94F779-C356-461B-B1CD-15BBF5FF6DE6.jpeg
1542152238_2333511085beb602e897888.45989064_F2BD4D1C-3388-4CBD-B41F-809BB8FA7768.jpeg
The clamp comes split at the bottom pic rail, and to cinch it tight it is dependent on your QD bipod mount or flashlight mount. Here I have my bipod mount attached, and it is snugged up tight. No loosey spin that comes about with some of these plastic clamp on deals that are around. Really a good looking addition to this Bully. The main purpose I got this was for light attachments, cause I mainly shoot from a rest vs a bipod.
 
1542215056_3087482355bec5590988225.57244710_E686A19F-A4AC-4893-A235-D7E9EE36619C.jpeg
Imold- I posted the bottle picatinny clamp link on page 2, 7th post down, on his tread. 

Couldnt sleep last night, so at around 1am I went out to the garage and tried this with bipod on to see if the clamp would slip and go cockeyed on me, but no go. This thing feels like it has some kind of suregrip on it cause it won’t budge. I tried to go more inward on the bottle, but the hatsan logo on the bottle adds just a hair of extra thickness to the circumference so it wouldn’t clamp on. I’m very happy with this mod, and it just adds to the look of the gun. Imold, if you do order one, just get the widest he offers, I think it was 45mm wide. Has 5 pic lugs. Make sure and tell him on the message box at checkout it is for a carbon fiber bottle at 61.50mm. His catalog shows for 60mm bottles, and those are for the steel bottles. Composite bottles like on our Bully’s are larger in diameter.
 
Ok thanks Augie. I’ll think it over for a bit and see how yours holds up, with my luck I’ll order it through PayPal and there won’t be a message box where I can tell him it’s for a carbon fiber bottle and needs to be 61.50 mm. I did put 60 mm and 45mm on his ordering site but like I said I’ll see how yours holds out after a tin or two of shooting.
 
B.Ragu,

I got the bully at midway for $544 on clearance in .25 caliber. I also swapped out the rail for the bull master. Cost me 15 dollars and 5 shipping from Hatsan USA. Also dialed down about 9 turns on spring, I might have 5 threads left to reduce off I had to. It's averaging 900 FPS with standard JSBs for about 45 ft/lbs. I'm busting ragged home groups at 35 yards or so.

I also ordered a picatinny mount picatinny extension rail from Amazon that's a tad shorter than the bull master rail, but looks like it would be stronger still! It attaches to the actual receiver front with 2 large bolts and nuts type mount. The front screw almost sits too far front, but it will work. It would need about 1/4" ground off the plastic outer part of that first rail mount on the stock to fit, but it's a beast. If bull master rail fails, is next, but.... so far so good!
 
Love the info in this thread. I have a Bully in .22 and will be doing a few mods as well. I'll be changing out the bottle to either a 580 cc or 800 cc bottle if they come back on stock. I noticed your fill port is different,looks like you have a fill nipple instead of tube regular probe. If so how'd you do it as I'd rather have a regular connection and not the fill probe. Here's a picture of the 800cc bottle will add a little weight but the plastic removed and rail should offset it or minimize the gain. 
1572446510_13935185525db9a12ec6e210.66334601_Screenshot_20191030-103739_Chrome.jpg

 

I have tried several bullets and round balls. This gun is very powerful but because of the scope rail I can't tell anything about consistent accuracy. I have tried Hatsan's 168gr and a 196gr from Nielsen, and round balls. I bought this gun to use for the Texas whitetail season and it does register 225fpe with the 196gr hollow point. I love the look of the gun and I have an idea to fix it if I have to, but I have requested my money back and I am waiting to see what Hatsan has to say. I wish they would do a recall and re design the rail.

I’ve got the .45 too. Haven’t mounted a scope to it yet. Just used the included peep site so haven’t ran into the accuracy issues you guys are seeing yet. When I felt the 10 lb. trigger and heard the deafening report I almost returned it on the spot. The sticky port cover didn’t help nor did the sharp edges everywhere. I cut myself cocking it.

Tried several different ammo sources but skipped the Hatsan which seemed entirely too short to fly well. All of them have the same problem. They shift in the magazine during recoil and and block magazine rotation. The 196 Nielsen’s and 200 Venturi hollowpoints did Ok, but the cowboy ammo was less accurate.

Was able to get the trigger pull down to 2lbs 14oz. but below that it isn’t safe, which matched the results on the YouTube video and is manageable for a hunting arm. There looks to be more opportunity there but it would require fabbing parts.

Going to design a 3D printed magazine cover that will snap on over the magazine to hold the rounds in place and remove that useless sticking port cover mess.

Looking into designing my own extension to the baffles to quiet it to a manageable level but haven’t come up with what I think would be a reliable connection/retention scheme yet.

Not confident in any of those plastic bands and risers. Don’t understand how they wouldn’t have thermal expansion poi shift issues. Will probably get rid off all of them and get an aluminum band machined to replace the rear one. With that and a rear riser bar could just bolt on a picatinny rail.

Lot of work for something that should have worked out of the box but don’t know of an equivalent .45/.50 repeater short of the on hold Umarex Hammer.
 
That’s the Bully of owning a Bully! I got rid of the mag and removed the actuator. Shoot it single-shot and can use longer slugs. Also removed the fill port crap. Replaced the Hatsan barrel and tightened the valve nut inside. The mad held 7. So that is what I use for a shot string. At 50 yards, all shots are within 1” of each other. But it is a brick when carrying. 
 
BigRagu - thanks for the post! aside from the scope rail, have you done any internal tuning? I've ported the unpressurized side of the valve and a little bit on the barrel and TP but haven't had time to even test shoot, as the O-rings are now leaking slowly I believe. Have you taken the valve out of the bottle by chance? wondering what type of material could be taken out there and maybe a spring swap. I have the .454 and the hammer spring is ridiculous - long, tight to the valve stem and heavy, would like to drop in a dual slingshot type spring set up and maybe change the hammer weight itself too. Lot of polishing needed on this rig, I did some on the trigger sear and cocking linkage but again, no time to really test for positive reports.
 
Having same issues. Frustrating, will stack 2-3 shots on top of each other and then next 3 will be right or left 3 inches? Ammo possibly? It also does not like the Neilson 48 gr slugs? I've shortened the rail and removed bottle shroud...it helped but still not what I was hoping for? Need a chrono to see what it's pushing. Feel like that will have some bearing on accuracy as well as you guys have mentioned. Thank you guys for sharing your experiences w this bully. I will get it there I think...just stinks it's not better out of the box. Hatsan should address these issues and give the bullmaster rail for free...