Benjamin Benjamin Bulldog M357 Impression

any love for the NSA .357 142 grain slugs? I bought some and they fit in the magazine no problem. I havent been able to test them because the neighbors will sh*t themselves. In fact I've gotta wait until spring, when I can get down south a little into the Panoche area.
NSA slugs tend to have thicker walls around their hollow point cavities in comparison to other slugs that this gun shoots well. I’m not so focused on their offerings at the moment.
 
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Looks to be a great gun< especially for folks without a 3/8 drill, and the inability to operate one, and a way to buy Pitbull, parts.

My Bulldog has been shooting at the m357 power range for several years, and has done so much of the time as a 24 inch barreled carbine. If you have a oem Bulldog 357, don’t sell it to buy a M357, do these steps.

Port the barrel and receiver to .30. Buy a Pitbull power spring and a steel charging handle to cock it.

Ditch the valve return spring as you reassemble.

Save $900+ bucks.

If you have to have the longer pressure tube, buy a Pitbull Airbow pressure tube which is rated higher by some, but not Benjamin, and fill a little higher. Myself the $335 price tag has stopped me. Hopefully the M357 pressure tube will be available at a cheaper cost.

The big news on this platform would be the Bulldog 257 if Benjamin ever gets it out to market.

Regards,

Roachcreek





 
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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.
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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)
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This is going back to Airgun Revision for repairs.
I would cut that spring away from the poppet valve and install it without the spring. That is how I am running my original bulldog now.
 
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More ammo testing. .357 Griffin Hollow point boattail slugs, 155 grain. These are the largest Griffin slugs that fit the .357 Bulldog/M357 Bulldog magazines without being too long for the mag to cycle. All heavier slugs will be single loaded by hand.
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All 5-shot shot strings were shot untethered and unregulated from 2900 psi - 2050psi.
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All groups shot seated behind a Caldwell turret rest atop a portable plastic shooting table at 50 yards. Below is the best of 3 groups. 1.5” CTC from 50 yards. The wind gusts are negligle at 50 yards with these slugs. Probably 3-5 mph gusts. I’m not reading wind, just shooting for chrono data.
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This group got screwed up because I adjusted my elevation turret the wrong way on the extremely low shot.
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Real world, average Joe shooting, no fluff. I haven’t done anything to the gun. First time shooting it since it came back from @Airgun-Revisions for repairs to the valve body that I effed up and posted about earlier in this thread. Thank you Rich for repairing and returning my rifle in a timely manner.
 
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Griffin hollow point boattails 165 grain slugs. Single loaded by hand. This photo with a slug in the mag is to demonstrate how it looks loaded in the mag. Mag will not cycle with these slugs. I tried them in both the stock magazine and a Matt’s Modded Mag from Pitbull Air, same result.
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With these heavier slugs it appears that as the pressure drops, the bullet drop becomes more pronounced as seen in the verticle pattern below. I’m not sure what happened to the 5th shot. I think I may have gone through the same hole as the fourth. I held over a little more on the final shot. Looks like two shots may have gone through the lowest shot about 1.5” below the bullseye.
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Griffin .357 hollow point boattail slugs 175 grain.
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Below is the only group I shot with the 175 grain Griffin boattail slugs. Looks to be about 1” CTC (maybe a little tighter) from 50 yards.
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I’ve noticed that when hand loading these, they may be slightly undersized or a little small for this barrel. Once they are pushed past the breech o-ring very little, if any, resistance is felt. I’m not sure if this is due to Rich throating the breech or if it directly correlates to the slugs’ diameter (.357). It was suggested that I slug this barrel. It may be time to do so. I’d also like to measure the diameter of these slugs. It may be time to test some .358 slugs. I’m not sure just yet considering I like how the 140-145 grain Griffin slugs shoot thus far, but this is the point of testing ammo. 185 grain Griffin boattails up next.

.357 Griffin hollow point boattail, 185 grain slugs.
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This group doesn’t look good but these slugs surprised me. I was told that the M357 couldn’t shoot 185 grain slugs.
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What surprises me is that I was able to adjust my holdover and hug the x axis of the grid (the horizontal line). My problem is the recoil of this gun. I’m gripping the gun tighter on some shots in attempt to better stabilize the gun, but still manage to move it causing my shots to move left and right, typically right. I have a bad habit of doing something that makes my shots go right, I may be gripping the gun too tightly. I want to work with these slugs more in the future. That first shot was cash money in terms of hitting a kill zone in the vitals. I wouldn’t run out and hunt with these just yet. I’m pretty rusty in general. I did adjust my holdover after the 3rd shot and brought the last two shots back up. From my experience today, I say don’t count out the 185 grain slugs. It seems to me that the M357 can shoot them just fine from 50 yards. This group was from a seated position in a plastic folding chair behind my portable shooting table using a Caldwell rest.

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Up next, .357 hollow point (with a large bb within the hollow point cavity), flat based, 145 grain Fireball slugs by Custom Solutions. These were purchased from @Airgun-Revisions when I purchased the rifle
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Losing daylight and both strings had a shot that didn’t register.
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Two targets quickly shot from 50 yards out.
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One thing that’s obvious about these Fireball slugs is that the hollow point diameter is larger than the Griffins. Consequently the holes in paper are larger. I’m assuming that the entry wound would be larger and if they expand well, the wound channel should open up even wider inside of an animal. Now that I have a baseline or at least an idea of how these projectiles shoot, I may start making hammer spring adjustments to see if I can improve or tighten up grouping with some of these slugs.
 
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Barrel cleaning. I think I put about 125-175 rounds through this M357 barrel. I haven’t cleaned it since I got it. Borescope photos of the barrel.

Crown
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photos of rifling
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Transfer port end/breech end. Rich told me he throated this barrel. I assume the scratches in these photos are from that process.
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Overall this barrel looks ok to me, not too leaded at all. Some grooves appear to catch lead along the length more than others. Time to clean it.

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After running a few dozen patches through the barrel it looks cleaner, but there are areas that patches aren’t reaching or cleaning well with a Patch Worm kit.

First patch
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Post pull-through cleaning photos of rifling
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Used patches
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Not sure about taking a brass brush to this barrel just yet. If it can’t take brass then I’ll give nylon a try. Borescopes come in handy to see how effective your barrel cleaning tools and methods are. A brush definitely looks necessary to clean the edges between the lands and grooves.

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Re-installed de-pinger and barrel supports since getting it back from being repaired. No pics of supports. Barrel supports and de-pinger came from @bthurman of Veradium Air. Below is a pic of the de-pinger installed before affixing the reservoir.
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On not using the valve spring in the bulldog. Just a bit of caution yes you can run the valve without valve spring to gain power but you are better off running a lighter spring. The bulldog will begin pushing the vale stem at an angle thru the valve body, valve stem stainless, valve body aluminum, point what happens is the top of the valve stem will begin to get a rough wear pattern on it due to no valve spring this prevents the valve from tracking straight thru the valve body as it opens and closes. this scraping will lead to the top of the valve body aluminum to be stuck to the valve stem creating more wear do to misaligment much quicker. This then just grinds away the aluminum valve body stem hole, this will eventually decrease power levels and slow the valve way down on open and close until the hole in valve body is oblong top to bottom. After firing a couple hundred rounds pull your valve stem and look to see if you are getting rough surface on it. If so replace it and the valve body to restore power and install a much lighter spring. This will help maintain the valve stem in the center of the valve body. Every bulldog that has come in to my shop with no valve spring displays this issue. The valve can no longer maintain a centered position, yes the valve will open and close but the power levels drop and it requires more hammer spring to get the dwell times because the valve stem and poppet are actually opening and closing at a slight angle.

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Looks to be a great gun< especially for folks without a 3/8 drill, and the inability to operate one, and a way to buy Pitbull, parts.

My Bulldog has been shooting at the m357 power range for several years, and has done so much of the time as a 24 inch barreled carbine. If you have a oem Bulldog 357, don’t sell it to buy a M357, do these steps.

Port the barrel and receiver to .30. Buy a Pitbull power spring and a steel charging handle to cock it.

Ditch the valve return spring as you reassemble.

Save $900+ bucks.

If you have to have the longer pressure tube, buy a Pitbull Airbow pressure tube which is rated higher by some, but not Benjamin, and fill a little higher. Myself the $335 price tag has stopped me. Hopefully the M357 pressure tube will be available at a cheaper cost.

The big news on this platform would be the Bulldog 257 if Benjamin ever gets it out to market.

Regards,

Roachcreek





Great advice there, could it be applied to the .457 Bulldog also? I'm also a bit gunshy of the Pitbull prices.
 
@c_m_shooter Unless something changed between last season and this season, that is incorrect. If you have evidence of the 300 ft/lb regulation that you speak of please post it.
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Source: https://tpwd.texas.gov/regulations/outdoor-annual/hunting/general-regulations/means-and-methods#:~:text=Air Guns and Arrow Guns&text=alligators, bighorn sheep, javelina,,pre-charged pneumatic air guns.
I recently harvested an 8pt buck at 100 yards. I shoot 142 grain Nielsen hollow points out of my M357. It looked like he had been shot with a 30-30. More than enough for Texas Whitetail.
 
I recently harvested an 8pt buck at 100 yards. I shoot 142 grain Nielsen hollow points out of my M357. It looked like he had been shot with a 30-30. More than enough for Texas Whitetail.
@Oakenhawk Consider posting photos of that hunt in the thread linked below