Would a heavier pellet save a scope from breaking....

[Mack The Knife]

....on a spring-piston air-rifle.

That is what we are going to find out.

I had mounted a new Bushnell Banner 4-12x40 on my HW97K which does an average of 910 ft./sec. (Pran, not 950 ft./sec. as posted in error earlier) with 8.64 grain H&N Field and Target Trophy. The scope must have been on the rifle for approximately 1 1/2 years and I have probably shot about 2,000 to 2,500 pellets since it was installed. Could be even double that but definitely not more.

Some months back the recoil knackered the scope and I have sent it to the U.S. for repairs. In the meanwhile I have asked Navdeep to get me another scope - a Bushnell Trophy 3-9x40. This is not the right scope for this rifle but I just couldn't stretch my budget to buy something more appropriate at the time of purchase.

Now, if I don't want this scope broken as well, I have two options open to me:
1) Reduce the power and hence the peculiar whiplash recoil springers generate by using a weaker main-spring or reduce the number of pre-load washers.

OR

2) Use a heavier pellet. In this case, the H&N Baracuda Match weighing in at 10.65 grains. 2 grains heavier than the rifle's usual diet.

I have decided to go with option # 2, even if it costs me another scope. I am a curious sod by nature.... The theory behind option no. 2 is that a heavier pellet will cause slightly lesser piston slam which can damage inappropriate optics.

I have two new tins of Baras totalling 1000 pellets and have decided to give them a go. Will order more when I get the opportunity.

So the bore has been cleaned and ten pellets chrono'd to get an average velocity of 816.60 ft./sec. (as opposed to 910 ft./sec. with the H&N FTTs) and a muzzle energy of 15.77 ft.lbs..

I will now try it for groups and if these pellets prove to be accurate then I will continue with the experimenting.

For the interim, I have mounted a Bushnell Lite-site scope which I have reparallaxed for airgun ranges.

If these pellets prove to be accurate and prevent the scope from going tits-up then there will be a hidden advantage to it. My HW80K does just over 800 ft./sec., so the holdovers for both rifles should be more or less the same.

More later.

Mack The Knife

[Vikram]

Most interesting.Been reading and learning Air rifles these days.Thanks Mack The Knife.

Best-
Vikram

[Mack The Knife]

Vikram,

Get yourself a copy of Gerald Cardew's "The Airgun From Trigger To Target". You may well get a used example of the Airgun BBS and it is a book that every gun nut should read.

What airgun literature/websites have you been reading lately?

Mack The Knife

[Vikram]

Sure Mack The Knife. Registered on AirgunBBS and been going through the pages there.Will try to get this book.Thanks once again.

Best-
Vikram

[dev]

Please do a check with some gsmith round heads, they are supposedly even more heavy. Will you be chronying the results? My QB is about to evolve into a .22 .

thanks in advance,

dev

....on a spring-piston air-rifle.

That is what we are going to find out.

I had mounted a new Bushnell Banner 4-12x40 on my HW97K which does an average of 910 ft./sec. (Pran, not 950 ft./sec. as posted in error earlier) with 8.64 grain H&N Field and Target Trophy. The scope must have been on the rifle for approximately 1 1/2 years and I have probably shot about 2,000 to 2,500 pellets since it was installed. Could be even double that but definitely not more.

Some months back the recoil knackered the scope and I have sent it to the U.S. for repairs. In the meanwhile I have asked Navdeep to get me another scope - a Bushnell Trophy 3-9x40. This is not the right scope for this rifle but I just couldn't stretch my budget to buy something more appropriate at the time of purchase.

Now, if I don't want this scope broken as well, I have two options open to me:
1) Reduce the power and hence the peculiar whiplash recoil springers generate by using a weaker main-spring or reduce the number of pre-load washers.

OR

2) Use a heavier pellet. In this case, the H&N Baracuda Match weighing in at 10.65 grains. 2 grains heavier than the rifle's usual diet.

I have decided to go with option # 2, even if it costs me another scope. I am a curious sod by nature.... The theory behind option no. 2 is that a heavier pellet will cause slightly lesser piston slam which can damage inappropriate optics.

I have two new tins of Baras totalling 1000 pellets and have decided to give them a go. Will order more when I get the opportunity.

So the bore has been cleaned and ten pellets chrono'd to get an average velocity of 816.60 ft./sec. (as opposed to 910 ft./sec. with the H&N FTTs) and a muzzle energy of 15.77 ft.lbs..

I will now try it for groups and if these pellets prove to be accurate then I will continue with the experimenting.

For the interim, I have mounted a Bushnell Lite-site scope which I have reparallaxed for airgun ranges.

If these pellets prove to be accurate and prevent the scope from going tits-up then there will be a hidden advantage to it. My HW80K does just over 800 ft./sec., so the holdovers for both rifles should be more or less the same.

More later.

Mack The Knife

[Mack The Knife]

Hi Div!

I have no intenion of using G Smith pellets in my airguns.

I do have chrono results somewhere. As mentioned above the velocity fell by approximatelty 100 ft./sec..

Other than this I haven't even zeroed-in the scope.

Mack The Knife

[shahid]

Mack The Knife a heavier pellet will definetely cause less scope abuse and consequental damage because of reduced piston slam. H & N Barracuda is a good pellet. Try it. It will significantly reduce scope damage.

Why don't you go in for a more solid construction scope for the HW 87 K like a Nikko Stirling, AGS, Simmons, Nikon, HAWKE or new BSA models ?

[dev]

Was that intentional the i before the e? .
Tell me one thing I have heard the ten m crowd say this that Indian pellet can wreck an air thingie...is it true? Cause my IZH just will not function with mastershot roundheads...I wanted to use something else than wad cutters for a change.

By the way is the good Doc somewhere in your neck of the woods? Haven't heard from him ever since he got a credit card .

Dev

Hi Div!

I have no intenion of using G Smith pellets in my airguns.

I do have chrono results somewhere. As mentioned above the velocity fell by approximatelty 100 ft./sec..

Other than this I haven't even zeroed-in the scope.

Mack The Knife

[LeadHead]

Hi
Most springers will cause scope damage.
One way to limit this is use Dampa Mounts.
But springers are old fashioned anyways.
Though I wont get into that argument....springers versus PCP.
Its like the Analogue V Digital reasoning in music.
The way forward is PCP and you dont have to worry about Scope Damage etc.
Also the damage could be limited by using special scopes meant for springers,
though I wonder if even thats a 100% solution.
Maybe the answer is to use scopes with PCP's and use your Springers without scopes.

Cheers
RJ

PS. regarding heavier pellets....thats a given with high powered PCP's

[Mack The Knife]

LeadHead,

Dampas don't always work on springers or even gasrams for that matter as they don't have the provision of an arrestor stud.

We can discuss that on another thread if you like. This topic deals with whether a heavier pellet can be used on a FAC rifle when there is no access to a spinger rated scope. Also, remember that not all springer rated scopes are equal. I have had a couple go tits-up on me.

Mack The Knife

[Mack The Knife]

Tell me one thing I have heard the ten m crowd say this that Indian pellet can wreck an air thingie...is it true?

I don't know about wrecking the gun but the way they are made I'd be surprised if they did not wreck the accuracy.

Asif is in Bombay setting up an ER unit for Fortis Hspital.

Mack The Knife