RAW Rapid RAW HM1000x Accuracy Issues

[forrest342]

I have the 25 caliber mini hunter, chassis version.

It’s shooting 3/4 to 1 inch groups at 50 yards using JSB, AEA and JTS 33-34 grain pellets. No real measurable accuracy difference between them. 825 ish FPS.

I’ve tried 2 different moderators and bare muzzle.

I called RAW and they suggested shooting at 100 yards to see how it groups. He said I may find the group size to be not much bigger at 100 than 50. He said this is possible because the pellet is still trying to stabilize at closer range because of precession and turbulence behind the pellet. (I’m paraphrasing him).
Has anyone ever experienced this phenomenon? It seems possible but unlikely to me.

He also suggested fine tuning the hammer spring by increasing tension. I’m hesitant to do this because the velocity spread impressively good. It seems like if turbulence behind the pellet was a problem decreasing the hammer would be the way to go, no?

 

[Ranchibi]

If yours has a LW non choked polygonal barrel then these barrels do well with higher speeds. I have a .22 RAW and it was tuned from the factory at 950fps with 25gr pellets, I have tuned mine to shoot 18gr pellets at 970fps. 825fps seems a bit too slow. I tried shooting the 18gr at 890fps and found the accuracy to be better at 970 FYI.

 

[rsfrid]

I agree with Randall. I was amazed at the speed of both the 22 cal and 25 cal RAWs and the accuracy. I'd suggest trying more different manufacturers pellets. Martin would probably tell you the 22 cal RAW is tuned for JSB 25 grain redesigns. I believe mine shoots around 945fps and does 3/8” to 1/2” groups at 50 yards. My 25 does approx 1” groups at 100 yards with 34 grain JSBs.

 

[forrest342]

Update for anyone interested. I appreciate your feedback.

I made some wind flags and did some more shooting. I shot at 100 yards for the first time with the RAW. I was able to shoot a 5 shot group that measured 1.125” and several others around 1.5”. There was a small amount of air movement so it’s certainly possible that it’s a 1 MOA gun indoors clamped in a vice. I’m satisfied with that.

Today I mostly shot at 50 but my last 3 shots of the day I stretched it out to 100. 5/8” group!

Funny thing is it’s still shooting .75” - 1” at 50 yards under the same conditions. I wouldn’t have expected to see respectable groups at 100 based on that. I still got a lot to learn I guess.

 

[mubhaur]

The gun has been tuned at 100 yards for extreme accuracy. When you come to 50 yards, the tuning gets compromised or you would need to readjust the hammer spring a bit for extreme accuracy at 50.

It is very routine phenomenon.

Bhaur

 

[forrest342]

The gun has been tuned at 100 yards for extreme accuracy. When you come to 50 yards, the tuning gets compromised or you would need to readjust the hammer spring a bit for extreme accuracy at 50.

It is very routine phenomenon.

Bhaur

Thats very interesting. Not something I would have expected.

 

[Hobbyman2007]

If you were to take those two fliers out of the groups . I’d say those are phenomenal for an out of the box rifle. The old saying stays true, you get what you pay for.

 

[Moonpie]

The gun has been tuned at 100 yards for extreme accuracy. When you come to 50 yards, the tuning gets compromised or you would need to readjust the hammer spring a bit for extreme accuracy at 50.

It is very routine phenomenon.

Bhaur

As I’m also a greenhorn to pcp tuning and etc, can you elaborate on the hammer spring adjustment procedure on this as I’m also a raw owner in .25 cal.
At 60 yards I’m doing great in the accuracy dept.
So why would I really do this adjustment?
Thanks!

 

[mubhaur]

As I’m also a greenhorn to pcp tuning and etc, can you elaborate on the hammer spring adjustment procedure on this as I’m also a raw owner in .25 cal.
At 60 yards I’m doing great in the accuracy dept.
So why would I really do this adjustment?
Thanks!

So that is a technical question. Although I am not a professional tuner but I do tuning for pleasure.

Accuracy is a combination of projectile, barrel, rpm of the projectile and fps.

Now if we keep the projectile and barrel constant, the rest of accuracy depends on fps and effective rpm.

Effective rpm are different from twist rate of barrel.

When a projectile is shot from a barrel, we need to achieve the best combination of fps and rpm of the projectile for extreme accuracy.

The actual phenomenon is that as the projectile moves forward, the rpm do not reduces as rapidly as the fps is reduced.

In order to keep the best combination of fps and rpm of the projectile, we need to maintain the best combination between the both.

If the accuracy is fine at 50 yards it means that rpm and fps combination is fine for that distance. But if you stretch to 100 yards, the rpm does not get slow down with same ratio as the fps slows down. This disturbs the effective combination of rpm and fps as well as accuracy.

That is why in order to achieve the best possible accuracy at any distance, the rpm and fps needs to be maintained for that distance.

One adjustment to achieve this combination is HST.

Bhaur

 

[Moonpie]

So that is a technical question. Although I am not a professional tuner but I do tuning for pleasure.

Accuracy is a combination of projectile, barrel, rpm of the projectile and fps.

Now if we keep the projectile and barrel constant, the rest of accuracy depends on fps and effective rpm.

Effective rpm are different from twist rate of barrel.

When a projectile is shot from a barrel, we need to achieve the best combination of fps and rpm of the projectile for extreme accuracy.

The actual phenomenon is the as the projectile moves forward, the rpm do not reduces as rapidly as the fps is reduced.

In order to keep the best combination of fps and rpm of the projectile, we need to maintain the best combination between the both.

If the accuracy is fine at 50 yards it means that rpm and fps combination is fine for that distance. But if you stretch to 100 yards, the rpm does not get slow down with same ratio as the fps slows down. This disturbs the effective combination of rpm and fps as well as accuracy.

That is why in order to achieve the best possible accuracy at any distance, the rpm and fps needs to be maintained for that distance.

One adjustment to achieve this combination is HST.

Bhaur

Thank you sir for the excellent explanation!
Think I’m going to leave mine alone! lol