PCP A RAW and in.357? Not a gun i would normally be looking at!

[Ezana4CE]

The design of a true diabolo pellet can’t scale much past about 81 grains in .357. Once you go heavier, the skirt has to be made thicker or the PSI from most .357 PCPs will blow out a thin pellet skirt. And as soon as you thicken the skirt, the diabolo shape is gone—the waist widens, the balance shifts rearward, and it stops behaving like a drag‑stabilized pellet. At that point it’s a hollow‑base slug, even if the tin calls it a pellet.

@Grunt64 I don't see it that way. I disagree with this assertion without solid supporting evidence.

 

[Grunt64]

@Grunt64 Not at all. I'm seeking factual information supporting your claim. It seems that what you're attempting to explain is a conclusion that you've drawn based upon...I don't know. I say that based upon how you are presenting your claims. Who has the authority to set the parameters governing how airgun projectiles are classified? Do you? Professional ballisticians (sp?)? Projectile manufacturers? Who is mandating that heavy pellets (or any pellets) have to have thin skirts?

In older writings, I've read all sorts of lead airgun projectiles being described as "pellets." However, in this discussion we're referring to diabolo pellets.

The authority isn’t me — it’s the geometry that defines a diabolo pellet. A true diabolo has three required features: a thin hollow skirt that can flare, a narrow waist, and a forward center of gravity. That’s the definition used by Hard Air Magazine, by JSB, H&N, Crosman, and every major pellet manufacturer.

Once you push a .357 projectile past roughly 81 grains, that geometry physically can’t exist anymore. The skirt has to be made thicker or the PSI from most .357 PCPs will blow out a thin pellet skirt. As soon as the skirt gets thick, the waist widens, the balance shifts rearward, and the projectile stops being drag‑stabilized. At that point it becomes a hollow‑base slug by design, even if a manufacturer or reseller still uses the word “pellet” on the label.

So the classification isn’t based on weight — it’s based on shape and how the projectile is stabilized in flight. The weight just makes the design change unavoidable once you get into the 110–120gr range.

 

[Grunt64]

@Grunt64 I don't see it that way. I disagree with this assertion without solid supporting evidence.

Every major pellet manufacturer uses that same shape because that’s what makes a pellet drag‑stabilized.

Once you go above about 81 grains in .357, the skirt can’t stay thin enough to flare without being damaged by the pressure spike from a PCP. The skirt has to be thickened, which shifts the center of gravity rearward and forces the waist to widen. At that point the projectile stops being a diabolo and becomes a hollow‑base slug, even if the label still says “pellet.”

So the classification isn’t based on weight — the weight just forces the shape to change. The shape is what determines whether it’s a pellet or a slug.

 

[Billm]

Well, for once I’m going to exercise some caution. I was all ready to point out that the 110gr AEA pellet depicted by Danman does indeed depict a wasp waisted Diabolo pellet. Then I came across a thread on AGN that shows a purchased 110gr tin next to the 80.8 gr .35 pellet and tin. Guess what: the pellet and the photo on the 110gr pellet do not show a Diabolo pellet. They show a cylindrical pellet somewhat similar to a classic Sheridan cylindrical pellet. Not quite a cylindrical slug, but darn close. Maybe the product images used by everyone are incorrect. One of you .357 owners needs to purchase a tin and settle this once and for all. Don’t force me into a corner, where I have to purchase another airgun, just to test this theory.

New aea 110 grain pellets

Going to try these huge 9mm pellets out, I'm curious. 110 grain next to an 81 grain.

www.airgunnation.com

 

[Ezana4CE]

Well, for once I’m going to exercise some caution. I was all ready to point out that the 110gr AEA pellet depicted by Danman does indeed depict a wasp waisted Diabolo pellet. Then I came across a thread on AGN that shows a purchased 110gr tin next to the 80.8 gr .35 pellet and tin. Guess what: the pellet and the photo on the 110gr pellet do not show a Diabolo pellet. They show a cylindrical pellet somewhat similar to a classic Sheridan cylindrical pellet. Not quite a cylindrical slug, but darn close. Maybe the product images used by everyone are incorrect. One of you .357 owners needs to purchase a tin and settle this once and for all. Don’t force me into a corner, where I have to purchase another airgun, just to test this theory.

New aea 110 grain pellets

Going to try these huge 9mm pellets out, I'm curious. 110 grain next to an 81 grain.

www.airgunnation.com

@Billm appreciate the thread reference in your quoted post. It prompted me to open my tin of AEA .35, 110 grain pellets. They are arguably Diabolo pellets. Depending upon what the criteria is, I could see the argument going either way.

I need to take a photo in better lighting.

 

[Billm]

I’d agree with that. Purely out of curiosity are the bases deep like a pellet skirt or more like a Corbin hollow base? From my point of view, I’m more interested in how they perform. The manufacturers don't help with the way they throw terminology around. I have some H&N Rabbit Magnum, H&N calls them domed pellets, they sure look like a cylindrical slug to me.

 

[Ezana4CE]

I’d agree with that. Purely out of curiosity are the bases deep like a pellet skirt or more like a Corbin hollow base? From my point of view, I’m more interested in how they perform. The manufacturers don't help with the way they throw terminology around. I have some H&N Rabbit Magnum, H&N calls them domed pellets, they sure look like a cylindrical slug to me.

@Billm They are shallow skirts. I don't know how they compare to MRDs Shallow base or cup base slugs in terms of skirt/base depth. I don't think I'd opened the tin until I took the photo. I have not shot any yet.

 

[Danman]

Well, for once I’m going to exercise some caution. I was all ready to point out that the 110gr AEA pellet depicted by Danman does indeed depict a wasp waisted Diabolo pellet. Then I came across a thread on AGN that shows a purchased 110gr tin next to the 80.8 gr .35 pellet and tin. Guess what: the pellet and the photo on the 110gr pellet do not show a Diabolo pellet. They show a cylindrical pellet somewhat similar to a classic Sheridan cylindrical pellet. Not quite a cylindrical slug, but darn close. Maybe the product images used by everyone are incorrect. One of you .357 owners needs to purchase a tin and settle this once and for all. Don’t force me into a corner, where I have to purchase another airgun, just to test this theory.

New aea 110 grain pellets

Going to try these huge 9mm pellets out, I'm curious. 110 grain next to an 81 grain.

www.airgunnation.com

Here we are battling it out and @Ezana4CE had then in his ammo collection the whole time
I was searching high and low for an actual pic of these pellets as you definitely cant always go by the image on the ammo lid. As I figured they look similar to Jsb Beast 33gr.
@Ezana4CE what gun do you plan to shoot these monsters out of?
Wonder if they'd fit in most magazines?

 

[Ezana4CE]

Here we are battling it out and @Ezana4CE had then in his ammo collection the whole time
I was searching high and low for an actual pic of these pellets as you definitely cant always go by the image on the ammo lid. As I figured they look similar to Jsb Beast 33gr.
@Ezana4CE what gun do you plan to shoot these monsters out of?

@Danman I thought I'd try them in my Rattler. My Rattler sucks shooting JSB .35, 81 grain diabolo pellets. I want to try shooting them in my Bulldog M357, maybe the original Bulldog .357.

 

[Ezana4CE]

Here we are battling it out and @Ezana4CE had then in his ammo collection the whole time
I was searching high and low for an actual pic of these pellets as you definitely cant always go by the image on the ammo lid. As I figured they look similar to Jsb Beast 33gr.
@Ezana4CE what gun do you plan to shoot these monsters out of?
Wonder if they'd fit in most magazines?

@Danman No battle in my eyes. I aim to seek good information. I've had them for a while. I'd actually forgotten about them until we started discussing this. I started another thread to continue this discussion so we don't continue to derail your thread.

What Makes a Diabolo Pellet A Diabolo Pellet? Who Sets the Parameters and Criteria Defining a Diabolo Pellet?

Feb 24, 2026

Just as the title states. They are questions I'd like answers to. This topic is a continuation of a thread that I participated in derailing beginning in post #10 here PCP - A RAW and in.357? Not a gun i would normally be looking at!
Revew from post #10 towards the end (post #27) for context. Some of the confusion in this thread came from differing photos used on AEA 110 grain .35 diabolo pellets. I'm looking for evidence-based claims that satisfy the questions. I'm also interested in what @Miles_M has to say on the topic. Grunt64 has made some interesting claims and Billm has...

• Ezana4CE

• 

 

[Zelos1]

Well, for once I’m going to exercise some caution. I was all ready to point out that the 110gr AEA pellet depicted by Danman does indeed depict a wasp waisted Diabolo pellet. Then I came across a thread on AGN that shows a purchased 110gr tin next to the 80.8 gr .35 pellet and tin. Guess what: the pellet and the photo on the 110gr pellet do not show a Diabolo pellet. They show a cylindrical pellet somewhat similar to a classic Sheridan cylindrical pellet. Not quite a cylindrical slug, but darn close. Maybe the product images used by everyone are incorrect. One of you .357 owners needs to purchase a tin and settle this once and for all. Don’t force me into a corner, where I have to purchase another airgun, just to test this theory.

New aea 110 grain pellets

Going to try these huge 9mm pellets out, I'm curious. 110 grain next to an 81 grain.

www.airgunnation.com

Bill, I think that you owe it to every subscriber here to “acquire” a .357, of your choice and commit to hours of shooting fun so that we can be assured that you are wrong and go buy our own in the name of science!

 

[SpindleB]

I believe this must have been modified to reach this power level. What i dont love about it is that its a bit of an odd duck for sure. They dont list a .357, you have to call and custom order one in that caliber. 120fpe is laughable on a .357, 220fpe is respectable. Wouldn't use it on large game/hunting (completely illegal here anyways with airguns) but it does seem plenty powerful, for reference that would be an 81gr pellet going just over 1100fps, OUCH. If its a slug only gun....thats a whole other path I dont really want to go down I do see AEA makes a heavy 110Gr .357 pellet now....ill keep this thread updated with what I find out!

I had a .357 for a short time.
Regulated with 82gr pellets it was 120FPE.
The regulator was iffy so I put in the HUMA and that brought it to 140FPE. But to get over 200fpe would require removing the regulator or adding significant amount of plenum.

That is the shortcoming of the RAW .357, regulated with limited plenum. The .357 has a barrel volume of around 40cc. If it were direct feed like AirForce then 120-160cc plenum would be optimal. But it is a poppet valve gun and poppet dwell is an unquantified variable. But 80cc plenum is where I would start.

I was not impressed with the rifle and sold it.

 

[Danman]

I had a .357 for a short time.
Regulated with 82gr pellets it was 120FPE.
The regulator was iffy so I put in the HUMA and that brought it to 140FPE. But to get over 200fpe would require removing the regulator or adding significant amount of plenum.

That is the shortcoming of the RAW .357, regulated with limited plenum. The .357 has a barrel volume of around 40cc. If it were direct feed like AirForce then 120-160cc plenum would be optimal. But it is a poppet valve gun and poppet dwell is an unquantified variable. But 80cc plenum is where I would start.

I was not impressed with the rifle and sold it.

Hey thanks for the reply, I was hoping you'd chime in! So low 800s with an 81gr pellet?....Yeah im not into that; I prefer a pcp these days to shoot standard (weight) pellets to at least 900fps.
The Huma reg is an excellent upgrade if ever needed for sure.
The RAW in question I'm looking at comes with a spare barrel, 3 mags, bipod, and custom buttstock plate thingy (I'm not sure i like that) The value is there for sure.

I emailed & called the dealer with a ton of questions but they are away for a few days and will get back to me.
Biggest question I have is how is it hitting 220fpe, and if it was regulated. Did RAW ever sell their pcps as unregulated? How many shots per fill were you getting @SpindleB ?

 

[SpindleB]

Hey thanks for the reply, I was hoping you'd chime in! So low 800s with an 81gr pellet?....Yeah im not into that; I prefer a pcp these days to shoot standard (weight) pellets to at least 900fps.
The Huma reg is an excellent upgrade if ever needed for sure.
The RAW in question I'm looking at comes with a spare barrel, 3 mags, bipod, and custom buttstock plate thingy (I'm not sure i like that) The value is there for sure.

I emailed & called the dealer with a ton of questions but they are away for a few days and will get back to me.
Biggest question I have is how is it hitting 220fpe, and if it was regulated. Did RAW ever sell their pcps as unregulated? How many shots per fill were you getting @SpindleB ?

Given my disappointment with the rifle I never got as far as shots per fill. A believe the huma was set to 180bar maybe 175bar.

I thought about building out a plenum (I did on the .25 HMX) but it isn't structurally sound which is why I took it off the .25.

.25 with plenums

 

[Danman]

Given my disappointment with the rifle I never got as far as shots per fill. A believe the huma was set to 180bar maybe 175bar.

I thought about building out a plenum (I did on the .25 HMX) but it isn't structurally sound which is why I took it off the .25.

.25 with plenums
View attachment 19787View attachment 19788

I found a company that makes the plenums and gives em a decent little boost in power for the smaller caliber rifles anyways... Looks a bit cleaner too: https://www.google.com/url?sa=t&sou...QQFnoECE4QAQ&usg=AOvVaw1qjJMH_Y0y9PYOmG9NTTsz

 

[SpindleB]

I found a company that makes the plenums and gives em a decent little boost in power for the smaller caliber rifles anyways... Looks a bit cleaner too: https://www.google.com/url?sa=t&sou...QQFnoECE4QAQ&usg=AOvVaw1qjJMH_Y0y9PYOmG9NTTsz

I used the RAW plenum and a huben power Dream Universal regulator. Still needed 1/4" to clear the stock. Luckily I had the Trajectron airforce insert that was 1/4".

But all the weight was hanging on the inlet of the gun.

Also the plenums do not work on LRT with that ugly fat moderator.