Benjamin Bulldog - The Search for Quiet and Accuracy

[wordsmith]

I recently bit the boolit (so to speak) and purchased a .357 Benjamin Bulldog, in the hopes of having a legit 100 yard coyote and coon / 50 yard small hog airgun. I'm not a fan of the looks, but it's sorta so ugly, it grows on you. Obligatory pics...





Half of my post deals with the quiet part...which this gun is not as delivered. In fact, it's surprisingly loud, sounding somewhat like an unsuppressed hypervelocity 22LR. Way too loud for the type of backyard shooting I'm used to with the .22/.25 Marauder. So I reached out to Matt at Pitbull Airguns to try out his brand new 3D-printed "long" moderator, shown in the pictures at the bottom. Cutting to the chase, it made a HUGE difference in perceived sound. The wife was very impressed, as she was kinda shocked the first time I shot the Bulldog in stock form. It's not Marauder quiet, but it's very manageable now. Matt was awesome to work with, and I mean awesome. Parts fit perfectly. Highly recommended.

So now to the second part, accuracy, which is an on-going effort I'm hoping others have tackled and can chime in. Being the control freak, self-reliant type, I wanted to find a boolit mold(s) so I can roll my own, and I wanted a cup / hollowpoint for hunting. NOE to the rescue except...I wanted the Bob's Boattail RG4 for 357, but there weren't any in sight. So I decided to try a more traditional design in the 150 SWC shape.



I somewhat reflexively went with 0.358 sizing and 2 coats of gold Hi-Tek coating (Gen 1) with a light tumble lube in 45-45-10 to ease the sizing effort, since I don't have the slippery Extreme Catalyst 2. I opted for pure Pb plus 2% pewter by weight, which turned out to be a poor choice for expansion.

On the first outing, things started acceptably (1-2" group at 50 yards), but after about 10 rounds, groups started to open up and after another 10 rounds, I couldn't hit the side of a barn at 100 yards. Groups were 2-3 ft at best. After returning home, I borescoped the barrel and saw pretty significant build-up of what appeared to be 45-45-10. I was able to clean it out without major effort, but lesson learned.

On the second outing (using FP-10 as a lubricant on 2x Hi-Tek coated rounds instead of 45-45-10), the groups were again about 1-2" at 50 yards...not what I was hoping for at all. While at it, I did some expansion testing using 2.5 gallon water jugs. Both the flatnose and cup-pointed boolits went through 2-3 2.5 gallon water jugs long ways and kept going into the dirt backstop. I was unable to recover any slugs, and the holes were caliber diameter, indicating zero expansion and a non-starter for my purpose.

Which leads me to today. Going back to the drawing board, I decided to cast a pure Pb boolit, with a light lubing of FP-10. I finally put the PID controller into action that I bought about 6 months ago, and I have to say...you owe it to yourself to get one. Once it was trained, it kept the pot temperature within +/- 3 degrees of target, which made casting much more predictable with my cheapie Lee 20 lb bottom pour.

I purchased 3 Lee push-through sizer dies, and modified them to put out boolits at 0.3588, 0.3575, and 0.3565, respectively, as measured with my Mitutoyo caliper (+/- 0.0001). I'll be testing them soon to see how the pure Pb does at the various diameters. Pic for fun...



I slugged my Bulldog and somewhat surprisingly got dimensions of 0.3568 / 0.3510. I for some reason expected more like 0.3575 or even 0.3580, but I guess that's why 1 test is worth a thousand theories. I slugged several rounds, including the 0.3565 round, and it fully "filled" the rifling, giving the same 0.3568 diameter as the others, while looking the best with minimal "smear". Testing will tell which shoots best, however.

I'll conclude by asking if anyone out there has already tackled this rifle and have positive results? There are some folks having great luck with AeroMagnum HP sized to 0.3585, and I may try some of those if I'm unsuccessful. Otherwise, I intend to post my results here and hopefully give back a little to this excellent forum. More to come...

[melloairman]

I have no experience with that rifle . But do own several BB rifles . I use dry slide or a spray silicon lube that dry's for bullet lube Auto parts stores carry it and it is some times called 5th wheel slide out lube . Do not know how fast you are pushing that soft lead . But I have seen it fowl a barrel after 2 or 3 shoots . What I have also noticed is if I run my bullets more than .001 over slugged size leading occurs rapidly .Hope this info helps .GL Marvin

[clodhopper]

Nice rifle, it looks almost like a stealth fighter.

Getting expansion at 800 feet per second is going to require very soft bullets with big holed, thin walled hollow points.

I do not have a 9mm/.357 air rifle but lust after one. The semi wad cutter and a full diameter .357 hole are pretty effective with .38special.

[jcwit]

I have no experience with that rifle . But do own several BB rifles . I use dry slide or a spray silicon lube that dry's for bullet lube Auto parts stores carry it and it is some times called 5th wheel slide out lube . Do not know how fast you are pushing that soft lead . But I have seen it fowl a barrel after 2 or 3 shoots . What I have also noticed is if I run my bullets more than .001 over slugged size leading occurs rapidly .Hope this info helps .GL Marvin

I used to shoot BB rifles also when I was a kid!

You sir are the only one I have seen on the internet referring to large caliber air guns as BB guns. LOL

[corbinace]

BB = Big Bore in this context. Airgun lingo.

[tkerrigan]

Today I did some tethered shooting with the Bulldog. Using 180gr .357 spitzer from Neilsenammo.com at 2900psi they did 772, 773, 770, 752fps. Using same bullet at .356 they did 791, 792,796,792fps. I didn't bother with the .357's after that. At 2700lbs it did 811, 817, 817fps or 269fpe. Not bad for a Bulldog. The grouping was pretty good also, the day before it did six groups from .875" to 1.435" at 57.5 yards. Regards, Tom

[54bore]

Today I did some tethered shooting with the Bulldog. Using 180gr .357 spitzer from Neilsenammo.com at 2900psi they did 772, 773, 770, 752fps. Using same bullet at .356 they did 791, 792,796,792fps. I didn't bother with the .357's after that. At 2700lbs it did 811, 817, 817fps or 269fpe. Not bad for a Bulldog. The grouping was pretty good also, the day before it did six groups from .875" to 1.435" at 57.5 yards. Regards, Tom

Nothing wrong with these numbers!

[GhostHawk]

No experience with big bore, although I am watching and listening intently.

My latest is a Hatsan 135 QE Vortex in .22 and I have been experimenting with BLL.

But as you found it is easy to overdo.

So I have discovered that a single lightly lubed "fouling shot" followed by 5 unlubed pellets is giving me good accuracy. IMO slightly better than no lube, but it may not be provable. As I have not gotten to the point of measuring groups. To me they seem tighter but I may not be remembering correctly.

On a good day in my 20 foot basement airgun range, I can go 3 for 3 on pushpins.

You know the brightly colored plastic tacs with the hourglass shape. I stick them into a board at the bottom. Makes a fairly small target. Have to have everything right to hit them. Hold, breathing, all of it.

I did work my way down to it, and it still gives me a kick when I take 3 shots and see 3 tacks vaporize.

I suspect you are going to want to go as low on bullet weight as possible. As it will get you more speed. For accuracy you may want to think domed or pointed.

[kbstenberg]

From your opening post.
Why are you using a second lube over the HiTec? Doesn't the HT give a slick enough surface to size? When you slugged your barrel was it a mis-numnbering of .3568/ 3510 ? No intent ment.

[wordsmith]

kbstenberg - I was using a second lube over Hi-Tek since I was an early adopter of Hi-Tek and only had the original catalyst, which was not very slippery and made resizing difficult. The new Catalyst-2 apparently leaves the boolits with high lubricity, and eliminates the need for supplemental lube. I just don't have any.

I have abandoned Hi-Tek altogether for these airgun boolits, as I believe it may be too hard and cause issues with bullet grip in the fast 1:14 twist on the Bulldog. It's only a theory at this point, and upcoming testing will tell the story.

[wordsmith]

Also, not sure what you meant by mis-numbering, but I provided both the lands / grooves measurements, as I thought that might be of some interest to folks. I carried to 4 decimal places since my caliper is capable, although I may not be.

[kbstenberg]

It was my misunderstanding. I thought both numbers were gruve dia. Now I understand.

[Randy C]

I have a old 22cal Benjamin pump with peep sights and would like to have a .357 Benjamin-my 22 will put 3 pellets touching, it resembles one hole at 25 feet in the garage, we use to have a shooting competition every week many years a go.

[MT Chambers]

Have you tried the JSB .35 cal. pellets? To use as a baseline for further tests??

[wordsmith]

So I got out to shoot the 3 pellets sizes, and was underwhelmed. Groups were 2-5 inches at 35 yards, depending on the sizing. Admittedly, it was windy and my rest wasn't great, but the releases were pretty good, and I got substantial vertical variation, so I'm pretty confident in the (lack of) results.

MT - I was planning to get some Aeromagnum pellets, along with the JSB's to make sure I don't have something else going on. I'll report back when I get a chance to baseline the rifle.