Mould to replicate these GM bullets?

[dromia]

Have you chronographed the good loads?

When you have a load that works and you are trying to replicate it with other components then using those different components assuming a the same bullet weight and that it fits at least 2 thou over groove diameter then look to loads that will give a similar velocity as a starting point.

There are a lot of variables in play which you need to reduce to get anything meaningful to build upon, I start with a soft cast bullet of the same weight sized as previously stated and a powder load that will give a similar velocity and take it from there.

With these loads I have found the bullet is the least important in terms of design you are looking for a FNRPFB, single generous grease groove and a crimping groove, 250 gns of your chosen alloy.

The only other thing is the case expanding you need a "M" style expander die with the first step being 1-2 thou under bullet diameter and the second step 1-2 thou over. Those sad tapered expanders are just about OK for hard cast abominations but will deform soft cast bullets 'pon seating so getting appropriate case mouth expansion for the alloy is essential as all the work in getting a bullet to fit can be lost when seated into too tight a case mouth.

[Whizzbang]

Have you chronographed the good loads?

When you have a load that works and you are trying to replicate it with other components then using those different components assuming a the same bullet weight and that it fits at least 2 thou over groove diameter then look to loads that will give a similar velocity as a starting point.

There are a lot of variables in play which you need to reduce to get anything meaningful to build upon, I start with a soft cast bullet of the same weight sized as previously stated and a powder load that will give a similar velocity and take it from there.

With these loads I have found the bullet is the least important in terms of design you are looking for a FNRPFB, single generous grease groove and a crimping groove, 250 gns of your chosen alloy.

The only other thing is the case expanding you need a "M" style expander die with the first step being 1-2 thou under bullet diameter and the second step 1-2 thou over. Those sad tapered expanders are just about OK for hard cast abominations but will deform soft cast bullets 'pon seating so getting appropriate case mouth expansion for the alloy is essential as all the work in getting a bullet to fit can be lost when seated into too tight a case mouth.

All good advice, thanks.

I'm not wed to any particular design, so long as it feeds and shoots well, and is safe in a tubular mag.

You know I hadn't considered an M style expander- just belling the mouth to avoid shaving. All my bullets have, of course, been softer than the GMs, so maybe they are being deformed.

[Whizzbang]

Have you chronographed the good loads?

When you have a load that works and you are trying to replicate it with other components then using those different components assuming a the same bullet weight and that it fits at least 2 thou over groove diameter then look to loads that will give a similar velocity as a starting point.

There are a lot of variables in play which you need to reduce to get anything meaningful to build upon, I start with a soft cast bullet of the same weight sized as previously stated and a powder load that will give a similar velocity and take it from there.

With these loads I have found the bullet is the least important in terms of design you are looking for a FNRPFB, single generous grease groove and a crimping groove, 250 gns of your chosen alloy.

The only other thing is the case expanding you need a "M" style expander die with the first step being 1-2 thou under bullet diameter and the second step 1-2 thou over. Those sad tapered expanders are just about OK for hard cast abominations but will deform soft cast bullets 'pon seating so getting appropriate case mouth expansion for the alloy is essential as all the work in getting a bullet to fit can be lost when seated into too tight a case mouth.

Any idea where to buy an appropriate size M die in the UK?

Do they come with a selection of "45" expander plugs or do I need to specify the two diameters I need (which you kindly stated, above).

I've found a 45R one on eBay in the US but it doesn't ship to UK nor does it say what size the expander is.

They seem uncommon but maybe I'm looking in the wrong places.

I notice that NOE make an insert for the Lee Universal expander (I have one) which they say turns it into an M-type die.

[Sim G]

45R is a rifle m die. 45P fir pistol.

Hannams always seemed to have a good selection of m dies. RCBS do molds that come close to your desired shape. I use a .358 180gn SIL.

[mag41uk]

Have you chronographed the good loads?

When you have a load that works and you are trying to replicate it with other components then using those different components assuming a the same bullet weight and that it fits at least 2 thou over groove diameter then look to loads that will give a similar velocity as a starting point.

There are a lot of variables in play which you need to reduce to get anything meaningful to build upon, I start with a soft cast bullet of the same weight sized as previously stated and a powder load that will give a similar velocity and take it from there.

With these loads I have found the bullet is the least important in terms of design you are looking for a FNRPFB, single generous grease groove and a crimping groove, 250 gns of your chosen alloy.

The only other thing is the case expanding you need a "M" style expander die with the first step being 1-2 thou under bullet diameter and the second step 1-2 thou over. Those sad tapered expanders are just about OK for hard cast abominations but will deform soft cast bullets 'pon seating so getting appropriate case mouth expansion for the alloy is essential as all the work in getting a bullet to fit can be lost when seated into too tight a case mouth.

Any idea where to buy an appropriate size M die in the UK?

Do they come with a selection of "45" expander plugs or do I need to specify the two diameters I need (which you kindly stated, above).

I've found a 45R one on eBay in the US but it doesn't ship to UK nor does it say what size the expander is.

They seem uncommon but maybe I'm looking in the wrong places.

I notice that NOE make an insert for the Lee Universal expander (I have one) which they say turns it into an M-type die.

Hannams are the Lyman importers. You could also try CDSG

[dromia]

The NOE "M" style expanders are the way to go as they give you a choice of diameters, the Lyman diameters are fixed and if they aren't correct for your bullets then they are not going to be effective.

[dodgyrog]

https://noebulletmolds.com/site/shop/43 ... cavity-pb/
Nearest I could find

[Whizzbang]

https://noebulletmolds.com/site/shop/43 ... cavity-pb/
Nearest I could find

Thanks but that's a .432 mould I think. (I'm after a 454 minimum.)

[Whizzbang]

The NOE "M" style expanders are the way to go as they give you a choice of diameters, the Lyman diameters are fixed and if they aren't correct for your bullets then they are not going to be effective.

Noted, thanks.

[Whizzbang]

The NOE "M" style expanders are the way to go as they give you a choice of diameters, the Lyman diameters are fixed and if they aren't correct for your bullets then they are not going to be effective.

I've ordered the appropriate NOE expanders and additional lee universal expander die with which to use them.

Having an extra die is going to bugger up my set-up on the Dillon; will have to crimp as a separate stage (unless I crimp in the seating die, which I stopped doing some time ago.) Not really a big deal until I forget to do it...

I've decided I'm not going to buy any new molds until I've tried everything to get my existing ones shooting.

Thanks for the help.