Benjamin Benjamin Bulldog M357 Impression

[Greg_E]

Fresh cast alloys can shrink in time, but normally pure lead are OK. And when I say in time, normally a couple days to weeks, not months to years.

You can get a powder coat system going and increase diameter with that, normally 0.002 to 0.003 inch growth.

 

[Ezana4CE]

Found this on eBay. Let’s see how it holds up. Doesn’t feel like much for $50. It’s made of 3D printed plastic.

 

[Ezana4CE]

More testing with JSB .35 Match Diabolo pellets 81.02 grain.

I double loaded a shot and had to omit that one from the string. Not sure if that’s where the 862 fps shot came in. I’m pretty sure I deleted a similar shot. I got distracted with phone calls from work coming in on my day off. I’ll get a better string in a moment.

Here’ a better string and phot of a 5-shot group.

5-shot group

Another 5-shot group w/the .35 JSB 81.02 gr

Data for a 10-shot group with Griffin 85 grain hollow point dish-base slugs. These say dish-base, but they appear to be cup base slugs. My last shot was a duplicate of 1060 fps that was not recorded in the string. I hate when this chronograph does that.

The slugs

I adjusted my elevation for the last 4 shots. Two of them were money.

It’s pretty hot right now. My drinking water is very warm having sat out in the sun. My phone keeps overheating and it’s covered with a towel while I’m shooting. The gun is hot, the table is hot, the chronograph is hot, SCBA tank is hot. In fact I think I’m getting an additional 100-200 psi due to the high ambient temperature (around 96F).

.357 Griffin 145 grain RBT slugs

Shot string after 5 shots tethered at 2800 psi.

5-shot group from 40 yards. First shot was used as a reference to adjust scope’s zero from the settings from a different projectile. The larger holes are from sighting in my scope with a different projectile.

The other 5 shots within the same shot string as above.

5-shot group. And yes, by viewing other photos I verified that the shot to the far left is from another group and it is. To see for yourself, check the lower right corner of my previous target photo. These are the 5 shots within the red circle. A little high, but an acceptable group.

Couple groups from 50 yards. I pulled the final shot my holding the gun loosely and that was in a Caldwell Turret rest. I’m still getting used to the recoil.

Another group from 50 yards, same ammo. My target looks this way because I thought that I was tethered, well I was, but the valve wasn’t opened wide enough and I didn’t use my reg. I caught it while changing mags. The reservoir was down to 2000 psi. So the gradual lowering of the shots was likely due to the reservoir shooting down its pressure with each shot.

I ran into issues when I moved back to 55 yards. I chose to walk my shots up using holdovers as opposed to re-zeroing the scope for this distance or dialing the shots. My reservoir/SCBA tank pressure was around 2700-2600 psi while shooting this group. The first shot hit just a tad beyond 4” low. I also decided to try shooting off of an over-the-bore bipod while tethered and I don’t have an adequate rear bag to accommodate the gun while tethered. Also, my bipod’s feet do not grip the table top at all. After a couple of shots, I put the rifle back in the turret rest.

 

[Ezana4CE]

Additionally, I changed scopes. I removed the Helos 2-12x42mm and mounted a Vector Continental 5-30x56mm FFP scope on this M357. I must say that I like this Continental a whole lot better on this gun. If I get rid of the scope it will be because the manufacturer did the same silly crap that they did with the Veyron 4-16x44 FFP IR by only illuminating the center dot as opposed to the entire reticle. Other than that, I like this scope. I am not a really a “clicker,” but these turrets click and feel nice enough for my purposes.

 

[Greg_E]

If I were you, I'd probably just stick with the Griffin ammo. You are getting good power and good accuracy.

That said, the package of my cast stuff is on the way. They said probably by Thursday which seems kind of slow for priority. I'll get you the tracking number when I remember to grab the receipt.

 

[RM.510bigbore]

Wow.I'm impressed with that light ammo 85 yr griffin at 1060 fps..That's flat shooting!!!!!! Also the 145 grain is pretty impressive....keep putting in the good work

 

[Greg_E]

I'll have to cast some new 8x grain ammo and give then a try in mine, probably the 88 grain solids, the hollow point pins of the mold bugs me (a lot). Though I think the pins are 0.150 so I might try dropping a copper plate BB in there to make a steel expander.

 

[Ezana4CE]

I was looking forward to testing some new ammo this evening, then it started raining just after I got halfway set up.

 

[Ezana4CE]

Worked on a few improvements on my M357. Once again @bthurman was helpful in navigating disassembly. It had been a while since I had to get into one of my Bulldogs. The main thing he pointed out was that once I removed the reservoir, the end cap towards the valve has a large hole for a 3/8” hex allen key that makes removal a breeze. I don’t recall encountering that before. Below is also something that is new to me. I’d never seen this triangular plastic piece within the but of the clamshell. Not sure what it does.

He also sent a depinger and some barrel supports for me to try.

Depinger

Barrel supports and 3D printed pic rail adapter installed. I like what he’s done with the barrel supports. Let’s see how much of a difference they make when I get back to testing ammo.

I’ve used two other depingers in the Bulldog platform. I’ve also used other aftermarket barrel supports, so when I present my findings based upon my experience there will be a comparative basis for what I see. Thanks again Brian.

After a little more testing and it won’t be long before this ‘Dog is ready to hunt. This version feels noticeably heavier than the .357 Bulldog when shoulder or carrying around by the grip.

 

[Ezana4CE]

Sooooo I effed up and I gotta own it. I scratched the valve, jacked up the poppet, valve stem, and valve spring. How? By placing the valve spring in backwards and shooting the gun. When I unscrewed the reservoir, the rear reservoir cap unscrewed from the breech block, exposing the valve spring. I don’t ever recall this happening in my other Bulldogs and I’ve installed and removed depingers from them without this happening. Once I picked up the breech block to move it out of my work space, the spring fell out and so did the valve stem and poppet. I didn’t pay close enough attention to the orientation of the spring when I put it back together and now I’m paying for it. First time for everything I guess. That spring is to be installed with the tapered end toward the poppet, wide end toward the reservoir. I have a few options for repairs, but I’m waiting to see which route I want to take. Unfortunately, this gun may not be ready for the deer season opener. Thankfully I have others.

Again, @bthurman of Veradium Air has been extremely helpful in answering my questions and taking time to impart his knowledge. When he saw photos of what I did, he had to laugh and I don’t blame him. I really can’t say enough good things about how he’s helped me with these guns over the last couple of years. I’ll keep y’all posted. It’s embarrassing, but if it keeps someone else from doing something like this then I’d say sharing this information is worth it.

 

[DirtyGator]

Bummer, sorry to hear that. Good thing you have a few more in the kennel for opening day.

 

[Ezana4CE]

In accordance with being transparent I felt compelled to share my blunder. After installing my depinger, I reassembled the gun. Considering the time of day, I rushed to reassemble my rifle so that I could get back to testing slugs. I put the valve spring in backwards. You don’t want to do this and here’s why. That valve stem is not coming out of that spring without damaging one or both.

Shooting with the spring in backwards you can scratch the valve body effectively rending the sealing surface useless (unless you know how to repair valves and make valve stems)

This is going back to Airgun Revision for repairs.

 

[Ezana4CE]

I miss my M357 Bulldog.

 

[mackeral5]

In accordance with being transparent I felt compelled to share my blunder. After installing my depinger, I reassembled the gun. Considering the time of day, I rushed to reassemble my rifle so that I could get back to testing slugs. I put the valve spring in backwards. You don’t want to do this and here’s why. That valve stem is not coming out of that spring without damaging one or both.
View attachment 389795

Shooting with the spring in backwards you can scratch the valve body effectively rending the sealing surface useless (unless you know hour to repair valves and make valve stems)
View attachment 389796

This is going back to Airgun Revision for repairs.

The mistake with the poppet spring is easy to make, thanks for sharing so perhaps others will not make it. It is nice to see that Crosman is finally porting the valve exhaust larger, at least that's what appears when looking into your pic. I like the triangle piece in the stock, it appears to be some type of reinforcement.

 

[Ezana4CE]

The mistake with the poppet spring is easy to make, thanks for sharing so perhaps others will not make it. It is nice to see that Crosman is finally porting the valve exhaust larger, at least that's what appears when looking into your pic. I like the triangle piece in the stock, it appears to be some type of reinforcement.

@mackeral5 It’s a valve stem, not a poppet. I thought ti corrected my misuse of terminology in my previous edit. I don’t want to mislead anyone. I really should have known better. I saw the wide end hanging out of the valve body before it fell out. I didn’t realize that it sat in there so loosely. I reinstalled it in a hurry to get back outdoors.

It’s money that I shouldn’t have had to spend, but repairs were affordable thanks to @Airgun-Revisions (where I purchased the gun). @bthurman of Veradium Air also offered to repair it and beef up the performance. I declined at the moment because I want to test the M357 as it came to me so that other members have realistic expectations if they decide to purchase one. Brian (Veradium) and Rich (Airgun Revisions) are great to talk to about the Bulldog and offer desirable services and upgrades.

And another thing. I tried cutting the valve spring to remove the valve stem. That is some thick and very hard steel. It’s a really robust spring. It’s thicker and longer than the original valve return spring in the .357 Bulldog. Obviously this M357 has a larger valve which explains an increase in power. I also noticed that it sports a blue hammer spring. The cocking lever if stiffer as a result, but the lever on the M357 doesn’t feel like it will bend like the old stock .357 Bulldog cocking levers. This blue spring reminds me of the aftermarket hammer springs that Pitbull Airguns sell.

 

[mackeral5]

@mackeral5 It’s a valve stem, not a poppet. I thought ti corrected my misuse of terminology in my previous edit. I don’t want to mislead anyone. I really should have known better. I saw the wide end hanging out of the valve body before it fell out. I didn’t realize that it sat in there so loosely. I reinstalled it in a hurry to get back outdoors.

It’s money that I shouldn’t have had to spend, but repairs were affordable thanks to @Airgun-Revisions (where I purchased the gun). @bthurman of Veradium Air also offered to repair it and beef up the performance. I declined at the moment because I want to test the M357 as it came to me so that other members have realistic expectations if they decide to purchase one. Brian (Veradium) and Rich (Airgun Revisions) are great to talk to about the Bulldog and offer desirable services and upgrades.

IF we really want to be precise, valve stem only applies to the steel piece, that is the valve stem.... Depending on who you ask or which manufacturer is naming the part, either term can be used. There is no embarrassment in using either or.....

Again, easy mistake to make when you're not in these guns every day. I believe you chose wisely in getting acclimated to the gun in OEM form prior to engaging in any serious modifications. Often times those modifications will shift the operating envelope one way or another and often times there is no returning back to OEM once modified. You will not know which way you want to go, if any, until you put the gun through its paces. Who knows, you may not want to make any changes.

From what I am seeing in your pics the current version has larger porting and a larger tube, this in itself is a tremendous improvement over the original model.

Does the current version have the removable transfer port restrictor like the old one did?

 

[Ezana4CE]

IF we really want to be precise, valve stem only applies to the steel piece, that is the valve stem.... Depending on who you ask or which manufacturer is naming the part, either term can be used. There is no embarrassment in using either or.....

Does the current version have the removable transfer port restrictor like the old one did?

@mackeral5 Thanks. I’m still trying to learn the correct terminology for parts of my airguns. I have no idea about the transfer port restrictor. I wouldn’t know what it was if I were looking at it. I’d have to ask Rich or Brian.

 

[mackeral5]

If you pull the barrel, and remove the rear barrel retention screw, look down into the transfer port. The old guns had a plastic sleeve or straw like piece that restricted the transfer port It helped when shooting lighter ammo to have more shots and a flatter string. Of course the older guns had smallish porting anyway, to increase power you would remove the transfer restrictor and drill the ports larger. I wonder if Crosman made the ports larger on your gun, but left kept the restrictor to let you choose between high energy, low shot count and lower energy higher shot count/flatter shot string.

The reason I ask this is your shots are very close in velocity for an unregulated gun, this leads me to believe crosman is restricting the transfer port. Just a curiosity.

 

[Airgun-Revisions]

If you pull the barrel, and remove the rear barrel retention screw, look down into the transfer port. The old guns had a plastic sleeve or straw like piece that restricted the transfer port It helped when shooting lighter ammo to have more shots and a flatter string. Of course the older guns had smallish porting anyway, to increase power you would remove the transfer restrictor and drill the ports larger. I wonder if Crosman made the ports larger on your gun, but left kept the restrictor to let you choose between high energy, low shot count and lower energy higher shot count/flatter shot string.

The reason I ask this is your shots are very close in velocity for an unregulated gun, this leads me to believe crosman is restricting the transfer port. Just a curiosity.

Anything you want to know about the gun just call me. My number is on the website. Probably too many questions to sit here to type. Easier to call.

 

[Airgun-Revisions]

If you pull the barrel, and remove the rear barrel retention screw, look down into the transfer port. The old guns had a plastic sleeve or straw like piece that restricted the transfer port It helped when shooting lighter ammo to have more shots and a flatter string. Of course the older guns had smallish porting anyway, to increase power you would remove the transfer restrictor and drill the ports larger. I wonder if Crosman made the ports larger on your gun, but left kept the restrictor to let you choose between high energy, low shot count and lower energy higher shot count/flatter shot string.

The reason I ask this is your shots are very close in velocity for an unregulated gun, this leads me to believe crosman is restricting the transfer port. Just a curiosity.

For the more Technical stuff that is.